Document submitted to conclude E.O.12866 Review

1

EO12866_CCR 2050-AE81 Final Preamble and Rule_20141218

6560-50-P

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 257 and 261

[EPA-HQ-RCRA-2009-0640; FRL-9149-4]

RIN-2050-AE81

HAZARDOUS AND SOLID WASTE MANAGEMENT SYSTEM; DISPOSAL OF COAL 

COMBUSTION RESIDUALS FROM ELECTRIC UTILITIES 

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

SUMMARY: The Environmental Protection Agency (EPA or the Agency) is publishing a final 

rule to regulate the disposal of coal combustion residuals (CCR) as solid waste under Subtitle D 

of the Resource Conservation and Recovery Act (RCRA). The available information 

demonstrates that the risks posed to human health and the environment by certain CCR 

management units warrant regulatory controls. EPA is finalizing national minimum criteria for 

existing and new CCR landfills and existing and new CCR surface impoundments and all lateral 

expansions consisting of location restrictions, design and operating criteria, groundwater 

monitoring and corrective action, closure requirements and post closure care, and recordkeeping, 

notification, and internet posting requirements. The rule requires any existing unlined CCR 

surface impoundment that is contaminating groundwater above a regulated constituent’s

groundwater protection standard to stop receiving CCR and either retrofit or close, except in 

limited circumstances. It also requires the closure of any CCR landfill or CCR surface 
Document submitted to conclude E.O.12866 Review

2

impoundment that cannot meet the applicable performance criteria for location restrictions or 

structural integrity. Finally, those CCR surface impoundments that do not receive CCR after the 

effective date of the rule, but still contain water and CCR will be subject to all applicable 

regulatory requirements, unless the owner or operator of the facility dewaters and installs a final 

cover system on these inactive units no later than three years from publication of the rule. EPA 

is deferring its final decision on the Bevill Regulatory Determination because of regulatory and 

technical uncertainties that cannot be resolved at this time. 

DATES: This final rule is effective on [INSERT DATE 180 DAYS AFTER THE DATE OF 

PUBLICATION IN THE FEDERAL REGISTER].

ADDRESSES: EPA has established three dockets for this regulatory action under Docket ID 

No. EPA-HQ-RCRA-2009-0640, Docket ID No. EPA-HQ-RCRA-2011-0392, and Docket ID 

No. EPA-HQ-RCRA-2012-0028. All documents in these dockets are available at

http://www.regulations.gov. Although listed in the index, some information is not publicly 

available, e.g., Confidential Business Information (CBI) or other information whose disclosure is 

restricted by statute. Certain other material, such as copyrighted material, is not placed on the 

Internet and will be publicly available only in hard copy form. Publicly available docket 

materials are available either electronically in http://www.regulations.gov or in hard copy at the 

OSWER Docket, EPA/DC, WJC West Building, Room 3334, 1301 Constitution Ave., NW, 

Washington, DC. The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday 

through Friday, excluding legal holidays. The telephone number for the Public Reading Room is 

(202) 566–1744, and the telephone number for the OSWER Docket is 202–566–0276.

FOR FURTHER INFORMATION CONTACT: For questions on technical issues: 

Alexander Livnat, Office of Resource Conservation and Recovery, Environmental Protection 
Document submitted to conclude E.O.12866 Review

3

Agency, 5304P; telephone number: (703) 308-7251; fax number: (703) 605-0595; email address: 

livnat.alexander@epa.gov, or Steve Souders, Office of Resource Conservation and Recovery, 

Environmental Protection Agency, 5304P; telephone number: (703) 308-8431; fax number: 

(703) 605-0595; email address: souders.steve@epa.gov. For questions on the regulatory impact 

analysis: Richard Benware, Office of Resource Conservation and Recovery, Environmental 

Protection Agency, 5305P; telephone number: (703) 308-0436; fax number: (703) 308-7904; 

email address: benware.richard@epa.gov. For questions on the risk assessment: Jason Mills, 

Office of Resource Conservation and Recovery, Environmental Protection Agency, 5305P; 

telephone number: (703) 305-9091; fax number: (703) 308-7904; email address: 

mills.jason@epa.gov.

For more information on this rulemaking please visit 

http://www.epa.gov/epawaste/nonhaz/industrial/special/fossil/index.htm.

SUPPLEMENTARY INFORMATION: 

A. Does this Action Apply to Me?

This rule applies to all coal combustion residuals (CCR) generated by electric utilities 

and independent power producers that fall within the North American Industry Classification 

System (NAICS) code 221112 and may affect the following entities: electric utility facilities and 

independent power producers that fall under the NAICS code 221112. The industry sector(s) 

identified above may not be exhaustive; other types of entities not listed could also be affected. 

The Agency’s aim is to provide a guide for readers regarding those entities that potentially could 

be affected by this action. To determine whether your facility, company, business, organization, 

etc., is affected by this action, you should refer to the applicability criteria discussed in Unit

VI.A. If you have any questions regarding the applicability of this action to a particular entity, 
Document submitted to conclude E.O.12866 Review

4

consult the person listed in the preceding FOR FURTHER INFORMATION CONTACT 

section.

B. What Actions Are Not Addressed in This Rule?

This rule does not address the placement of CCR in coal mines. The U. S. Department of 

Interior (DOI) and, as necessary, EPA will address the management of CCR in minefills in 

separate regulatory action(s), consistent with the approach recommended by the National 

Academy of Sciences, recognizing the expertise of DOI’s Office of Surface Mining Reclamation 

and Enforcement in this area. See Unit VI for further details. This rule does not regulate 

practices that meet the definition of a beneficial use of CCR. Beneficial uses that occur after the 

effective date of the rule need to determine if they comply with the criteria contained in the 

definition of “beneficial use of CCRs.” This rule does not affect past beneficial uses (i.e., uses 

completed before the effective date of the rule.) See Unit VI for further details on proposed 

clarifications of beneficial use. Furthermore, CCR from non-utility boilers burning coal are also 

not addressed in this final rule. EPA will decide on an appropriate action for these wastes 

through a separate rulemaking effort. See Unit IV of this notice for further details. Finally, this 

rule does not apply to municipal solid waste landfills (MSWLFs) that receive CCR for disposal 

or use as daily cover.

C. The Contents of This Preamble Are Listed in the Following Outline 

I. Executive Summary

II. Statutory Authority

III. Background

IV. Bevill Regulatory Determination Relating to CCR from Electric Utilities and Independent 

Power Producers

V. Development of the Final Rule – RCRA Subtitle D Regulatory Approach

VI. Development of the Final Rule – Technical Requirements

VII. Summary of Major Differences between the Proposed and Final Rules

VIII. Implementation Timeframes for Minimum National Criteria and Coordination with 

Steam Electric ELG Rule 
Document submitted to conclude E.O.12866 Review

5

IX. Implementation of the Minimum Federal Criteria and State Solid Waste Management 

Plans

X. Risk Assessment

XI. Summary of Damage Cases

XII. Summary of Regulatory Impact Analysis

XIII. Uniquely Associated Wastes

XIV. Statutory and Executive Order Reviews

I. Executive Summary

This rule establishes nationally applicable minimum criteria for the safe disposal of coal 

combustion residuals in landfills and surface impoundments. This section summarizes these 

criteria. Detailed discussions of the criteria and the Agency’s rationale for finalizing these 

requirements are provided in Unit VI of this notice.

A. What are coal combustion residuals?

Coal combustion residuals (CCR) are generated from the combustion of coal, including 

solid fuels classified as anthracite, bituminous, subbituminous, and lignite, for the purpose of 

generating steam for the purpose of powering a generator to produce electricity or electricity and 

other thermal energy by electric utilities and independent power producers. CCR includes fly 

ash, bottom ash, boiler slag, and flue gas desulfurization materials. A description of the types of 

CCR can be found in the proposed rule (see 75 FR 35137).

CCR is one of the largest industrial waste streams generated in the U.S. In 2012, over 

470 coal-fired electric utilities burned over 800 million tons of coal, generating approximately 

110 million tons of CCR in 47 states and Puerto Rico. CCR may be generated wet or dry;

however, this composition may change after generation. Some CCR is dewatered while other 

CCR is mixed with water to facilitate transport (i.e., sluiced). CCR can be sent off-site for 

disposal or beneficial use or disposed in on-site landfills or surface impoundments. In 2012, 

approximately 40 percent of the CCR generated was beneficially used, with the remaining 60
Document submitted to conclude E.O.12866 Review

6

percent disposed in surface impoundments and landfills. Of that 60 percent, approximately 80

percent was disposed in on-site disposal units. CCR disposal currently occurs at over 310 active 

on-site landfills, averaging over 120 acres in size with an average depth of over 40 feet, and at 

over 735 active on-site surface impoundments, averaging over 50 acres in size with an average 

depth of 20 feet. 

B. Background

The Agency first solicited comments on the regulation of CCR in a proposed rule 

published in the Federal Register on June 21, 2010. This proposal, under the Resource 

Conservation and Recovery Act (RCRA), addressed the risks from disposal of CCR generated 

from the combustion of coal at electric utilities and from independent power producers. Two 

regulatory options were proposed. Under the first option, EPA proposed to list CCR as special 

waste subject to regulation under subtitle C of RCRA, when destined for disposal in landfills or 

surface impoundments. Under this option, CCR would require “cradle-to-grave” management 

and would be subject to requirements for, among other things, composite liners, groundwater 

monitoring, structural stability requirements, corrective action, closure/post closure care and 

financial assurance. States would be required to adopt the rule before it went into effect and a 

permitting program would be established with direct federal oversight. The subtitle C option, as 

proposed, would also effectively result in the closure of all CCR surface impoundments.

Under the second option, EPA proposed to regulate the disposal of CCR under subtitle D 

of RCRA by issuing minimum national criteria. Similar to the subtitle C option, this option 

would require composite liners, groundwater monitoring, structural stability requirements, 

corrective action, and closure/post closure care. However, consistent with the available statutory 

authority under subtitle D, EPA proposed this option to be a self-implementing rule with no 
Document submitted to conclude E.O.12866 Review

7

direct federal oversight, with an effective date six months after publication in the Federal 

Register. This option required all unlined surface impoundments to either retrofit to a composite 

liner or close within five years. 

After reviewing all the comments and additional data received, EPA is promulgating this 

final rule to regulate the disposal of CCR as solid waste under subtitle D of RCRA. This rule 

addresses the risks from structural failures of CCR surface impoundments, groundwater 

contamination from the improper management of CCR in landfills and surface impoundments 

and fugitive dust emissions. The rule has also been designed to provide electric utilities and 

independent power producers generating CCR with a practical approach for implementation of 

the requirements and has established implementation timelines that take into account, among 

other things, other upcoming regulatory actions affecting electric utilities and site specific 

practical realities. In order to ease implementation of the regulatory requirements for CCR units 

with state programs, EPA is also providing the opportunity for states to secure approval of its 

CCR program through the State Solid Waste Management Program (“SWMP”). EPA strongly 

recommends that States take advantage of this process by revising their SWMPs to address the 

issuance of the revised federal requirements in this final rule, and to submit revisions of these 

plans to EPA for review. EPA would then review and approve the revised SWMPs provided they 

demonstrate that the minimum federal requirements in this final rule will be met. In this way, 

EPAs approval of a revised SWMP signals EPA’s opinion that the State SWMP meets the 

minimum federal criteria. 

C. What types of CCR units are covered by this rule?

The final rule applies to owners and operators of new and existing landfills and new and 

existing surface impoundments, including all lateral expansions of landfills and surface 
Document submitted to conclude E.O.12866 Review

8

impoundments that dispose or otherwise engage in solid waste management of CCR generated 

from the combustion of coal at electric utilities and independent power producers. The 

requirements of the rule also apply to CCR units located off-site of the electric utilities’ or 

independent power producers’ facilities that receive CCR for disposal. In addition, the rule 

applies to certain inactive CCR surface impoundments (i.e., units not receiving CCR after the 

effective date of the rule) at active electric utilities’ or independent power producers’ facilities, 

regardless of the fuel currently used at the facility to produce electricity (e.g., coal, natural gas, 

oil), if the CCR unit still contains CCR and liquids.

The requirements do not apply to: (1) CCR landfills that ceased receiving CCR prior to 

the effective date of the rule; (2) CCR units at facilities that have ceased producing electricity (or 

electricity and other thermal energy) prior to the effective date of the rule; (3) CCR generated at 

facilities that are not part of an electric utility or independent power producer, such as 

manufacturing facilities, universities, and hospitals; (4) fly ash, bottom ash, boiler slag, and flue 

gas desulfurization materials, generated primarily from the combustion of fuels (including other 

fossil fuels) other than coal, for the purpose of generating electricity unless the fuel burned 

consists of more than fifty percent coal on a total heat input or mass input basis, whichever 

results in the greater mass feed rate of coal; (5) CCR that is beneficially used; (6) CCR 

placement at active or abandoned underground or surface coal mines; or (7) municipal solid 

waste landfills (MSWLF) that receive CCR.

D. What minimum national criteria are being established for CCR landfills and CCR surface 

impoundments?

This final rule establishes minimum national criteria for CCR landfills, CCR surface 

impoundments, and all lateral expansions of CCR units including location restrictions, liner 
Document submitted to conclude E.O.12866 Review

9

design criteria, structural integrity requirements, operating criteria, groundwater monitoring and 

corrective action requirements, closure and post-closure care requirements, and recordkeeping, 

notification, and internet posting requirements. 

1. Location Restrictions. To ensure there will be no reasonable probability of adverse 

effects on health or the environment from the disposal of CCR in CCR landfills, CCR surface 

impoundments, and all lateral expansions of CCR landfills and CCR surface impoundments 

(together “CCR units”), this final rule establishes five location restrictions. The location criteria 

include restrictions relating to placement of CCR above the uppermost aquifer, in wetlands, 

within fault areas, in seismic impact zones, and in unstable areas. All of these location 

restrictions require the owner or operator of a CCR unit to demonstrate that they meet the 

specific criteria. As discussed elsewhere in this preamble, the five location restrictions apply to 

all new CCR landfills, all new and existing CCR surface impoundments, and all lateral 

expansions of CCR units; however, existing CCR landfills are only subject to the location 

restriction for unstable areas. Units that do not meet these restrictions can retrofit or make 

appropriate engineering demonstrations to meet this criteria. This final rule requires owner or 

operators of existing CCR units that cannot make the required demonstrations to close, while 

owners or operators of new CCR units and all lateral expansions who fail to make the required 

demonstrations are prohibited from placing CCR in the CCR unit.

2. Liner Design Criteria. The final rule also establishes liner design criteria to help prevent 

contaminants in CCR from leaching from the CCR unit and contaminating groundwater. All 

new CCR landfills, new CCR surface impoundments, and lateral expansions of CCR units must 

be lined with composite liner, which is a liner system consisting of two components – a 

geomembrane and a two-foot layer of compacted soil – installed in direct and uniform contact 
Document submitted to conclude E.O.12866 Review

10

with one another. The final rule allows an owner or operator to construct a new CCR unit with an 

alternative composite liner, provided the alternative composite liner performs no less effectively 

than the composite liner. In addition, new landfills are required to operate with a leachate 

collection and removal system which is designed to remove excess leachate that may accumulate 

on top of the composite (or alternative composite) liner. Existing CCR landfills are not required 

to close or retrofit with a composite (or alternative composite) liner and a leachate collection and 

removal system. These existing CCR units can continue to receive CCR after this rule is in 

effect; however, the CCR units must meet all applicable groundwater monitoring and corrective 

action criteria to address any groundwater releases promptly. Existing CCR surface 

impoundments can also continue to operate as designed. However, if the existing CCR surface 

impoundment was not constructed with a composite (or alternative composite) liner or with at 

least two feet of compacted soil with a specified hydraulic conductivity, the rule would require 

the unit to retrofit or close. If such a CCR surface impoundment detects concentrations of one or 

more constituents listed in Appendix IV at statistically significant levels above the groundwater 

protection standard established by the rule, the CCR unit must retrofit or close.

3. Structural Integrity Requirements. To help prevent the damages associated with structural 

failures of CCR surface impoundments, the final rule establishes structural integrity criteria for 

new and existing surface impoundments (and all lateral expansions of them) as part of the design 

criteria. While the applicability of the structural integrity requirements to individual CCR 

surface impoundments vary depending on factors such as dike heights and the potential for loss 

of life, environmental damage and economic loss if there is a dike failure, the final rule 

establishes requirements for owner or operators to conduct a number of structural integrityrelated assessments regularly. These include: conducting periodic hazard potential classification 
Document submitted to conclude E.O.12866 Review

11

assessments to assess the potential adverse incremental consequences that would occur if there 

was a failure of the CCR surface impoundment; conducting periodic structural stability 

assessments by a qualified professional engineer to document whether the design, construction, 

operation and maintenance is consistent with recognized and generally accepted good 

engineering practices; and conducting periodic safety factor assessments to document whether 

the CCR unit achieves minimum factors of safety for slope stability. If a CCR unit required to 

conduct a safety factor assessment fails to demonstrate that the unit achieves the specified factors 

of safety, the owner or operator must close the unit. In addition, certain CCR surface 

impoundments are required to develop an emergency action plan which defines the events and 

circumstances involving the CCR unit that represent an emergency and identifies the actions that 

will be taken in the event of a safety emergency.

4. Operating Criteria. The operating criteria include air criteria for all CCR units, run-on 

and run-off controls for CCR landfills, hydrologic and hydraulic capacity requirements for CCR 

surface impoundments, and periodic inspection requirements for all CCR units. These criteria 

address the day-to-day operations of CCR units and are established to prevent health and 

environmental impacts from CCR units. The air criteria address the pollution caused by 

windblown dust from CCR units, and require owners and operators to minimize CCR from 

becoming airborne at the facility. The run-on controls for CCR landfills minimize the amount of 

surface water entering the unit that will help prevent erosion, surface discharges of CCR in 

solution or suspension, and will mitigate the generation of landfill leachate, while run-off 

controls help prevent erosion, protect downstream surface water from releases from the unit, and 

minimize stormwater runoff volume and velocity. CCR surface impoundments are subject to 

hydrologic and hydraulic capacity requirements to ensure the unit can safely handle flood flows, 
Document submitted to conclude E.O.12866 Review

12

which will help prevent uncontrolled overtopping of the unit or erosion of the materials used to 

construct the surface impoundment. The final rule also requires periodic inspections of CCR 

units to identify any appearance of structural weakness or other conditions that are not consistent 

with recognized and generally accepted good engineering standards.

5. Groundwater Monitoring and Corrective Action. The groundwater and corrective action 

criteria require an owner or operator of a CCR unit to install a system of monitoring wells and 

specify procedures for sampling these wells, in addition to methods for analyzing the 

groundwater data collected, to detect the presence of hazardous constituents (e.g., toxic metals) 

and other monitoring parameters (e.g., pH, total dissolved solids) released from the units. The 

final rule establishes a groundwater monitoring program consisting of detection monitoring, 

assessment monitoring and corrective action. Once a groundwater monitoring system and 

groundwater monitoring program has been established for a CCR unit under the rule, the owner 

or operator must conduct groundwater monitoring and, if the monitoring demonstrates 

exceedance of drinking standards for identified constituents in CCR, corrective action throughout 

the active life and post-closure care period of the CCR unit.

6. Closure and Post Closure Requirements. The closure and post-closure care criteria 

require all CCR units to close in accordance with specified standards and to monitor and 

maintain the units for a period of time after closure, including the groundwater monitoring and 

corrective action programs. These criteria are essential to ensuring the long-term safety of 

closing CCR units. Closure of a CCR unit must be completed either by leaving the CCR in place 

and installing a final cover system or through removal of the CCR and decontamination of the 

CCR unit. The final rule establishes timeframes to initiate and complete closure activities, and 

authorize owners or operators to obtain time extensions due to circumstances beyond the 
Document submitted to conclude E.O.12866 Review

13

facility’s control. As discussed elsewhere in this preamble, the rule also establishes alternative 

closure procedures in situations where an owner or operator is closing a CCR unit, but has no 

alternative CCR disposal capacity or is permanently closing the coal-fired boiler unit in the 

foreseeable future. Finally, owners and operators are required to prepare closure and post-closure 

care plans describing these activities.

7. Record Keeping, Notification, and Internet Posting Requirements. The final rule requires 

owner or operators of CCR units to record certain information in the facility’s operating record. 

In addition, owners and operators are required to provide notification to States and/or appropriate 

Tribal authorities when the owner or operator places information in the operating record, as well 

as to maintain a publicly accessible internet site for this information.

The following tables provide a summary of the specific technical requirements applicable 

to existing and new CCR landfills, existing and new CCR surface impoundments, and all lateral 

expansions of CCR units.
Document submitted to conclude E.O.12866 Review

14

CCR Landfill Requirements

Requirement

Existing CCR Landfills New CCR Landfills and Lateral Expansions

Required? 1 Rule Section Required? 1 Rule Section

Location Restrictions: √ §257.64 √ §257.60 - §257.64

Placement Above the Uppermost Aquifer √ §257.60

Wetlands √ §257.61

Fault Areas √ §257.62

Seismic Impact Zones √ §257.63

Unstable Areas √ §257.64 √ §257.64

Design Requirements: √ §257.70

Composite Liner √ §257.70 (b & c)

Leachate Collection and Removal System √ §257.70 (d)

Groundwater Monitoring and Corrective Action √ §257.90 - §257.98 √ §257.90 - §257.98

Weekly Inspections √ §257.84 (a) √ §257.84 (a)

Annual Inspections √ §257.84 (b) √ §257.84 (b)

Fugitive Dust Controls √ §257.80 √ §257.80

Run-on, Run-off Controls √ §257.81 √ §257.81

Surface Water Protection2 √ §257.3-3 √ §257.3-3

Closure Requirements √ §257.100 - §257.103 √ §257.100 - §257.103

Post-Closure Care √ §257.104 √ §257.104

Recordkeeping Requirements √ §257.105 √ §257.105

Notification Requirements √ §257.106 √ §257.106

Publicly Accessible Internet Site Requirements √ §257.107 √ §257.107

1 √ = required, = not required.

2

In existing regulations at 40 CFR part 257, subpart A.
Document submitted to conclude E.O.12866 Review

15

CCR Surface Impoundment Requirements

Requirement

Existing Surface Impoundments New Surface Impoundments and Lateral Expansions

Five feet high AND 20 acre-feet, or 20 feet high Five feet high AND 20 acre-feet, or 20 feet high

Yes No Yes No

Required? 1 Rule Section Required? 1 Rule Section Required? 1 Rule Section Required? 1 Rule Section

Location Restrictions: √

 §257.60 -

§257.64 √

 §257.60 -

§257.64 √

 §257.60 -

§257.64 √

 §257.60 -

§257.64

Placement Above the Uppermost Aquifer √ §257.60 √ §257.60 √ §257.60 √ §257.60

Wetlands √ §257.61 √ §257.61 √ §257.61 √ §257.61

Fault Areas √ §257.62 √ §257.62 √ §257.62 √ §257.62

Seismic Impact Zones √ §257.63 √ §257.63 √ §257.63 √ §257.63

Unstable Areas √ §257.64 √ §257.64 √ §257.64 √ §257.64

Design Requirements: √ §257.71 √ §257.71 √ §257.72 √ §257.72

Composite Liner 2 §257.71 2 §257.71 √ §257.72 √ §257.72

Leachate Collection and Removal System

Groundwater Monitoring and Corrective Action √

 §257.90 -

§257.98 √

 §257.90 -

§257.98 √

 §257.90 -

§257.98 √

 §257.90 -

§257.98

Structural Integrity Criteria: √

§257.73 & 

§257.83 √

§257.73 & 

§257.83 √

§257.74 & 

§257.83 √

§257.74 & 

§257.83

History of Construction √ §257.73 (c)

Construction Plan √ §257.74 (c)

Marker 3 √ §257.73 (a)(1) √ §257.73 (a)(1) √ §257.74 (a)(1) √ §257.74 (a)(1)

Hazard Potential Classification Assessments 3 √ §257.73 (a)(2) √ §257.73 (a)(2) √ §257.74 (a)(2) √ §257.74 (a)(2)

Structural Stability Assessments √ §257.73 (d) √ §257.74 (d)

Safety Factor Assessments √ §257.73 (e) √ §257.74 (e)

Emergency Action Plan 3 √ §257.73 (a)(3) √ §257.73 (a)(3) √ §257.74 (a)(3) √ §257.74 (a)(3)

Weekly Inspections √ §257.83 (a) √ §257.83 (a) √ §257.83 (a) √ §257.83 (a)

Annual Inspections √ §257.83 (b) √ §257.83 (b)

Fugitive Dust Controls √ §257.80 √ §257.80 √ §257.80 √ §257.80

Hydrologic & Hydraulic Capacity Requirements √ §257.82 √ §257.82 √ §257.82 √ §257.82

Surface Water Protection 4 √ §257.3-3 √ §257.3-3 √ §257.3-3 √ §257.3-3
Document submitted to conclude E.O.12866 Review

16

CCR Surface Impoundment Requirements

Requirement

Existing Surface Impoundments New Surface Impoundments and Lateral Expansions

Five feet high AND 20 acre-feet, or 20 feet high Five feet high AND 20 acre-feet, or 20 feet high

Yes No Yes No

Required? 1 Rule Section Required? 1 Rule Section Required? 1 Rule Section Required? 1 Rule Section

Closure Requirements √

 §257.100 - 

§257.103 √

 §257.100 - 

§257.103 √

 §257.100 - 

§257.103 √

 §257.100 - 

§257.103

Post-Closure Care √ §257.104 √ §257.104 √ §257.104 √ §257.104

Recordkeeping Requirements √ §257.105 √ §257.105 √ §257.105 √ §257.105

Notification Requirements √ §257.106 √ §257.106 √ §257.106 √ §257.106

Publicly Accessible Internet Site Requirements √ §257.107 √ §257.107 √ §257.107 √ §257.107

1 √ = required, = not required.

2 Existing CCR surface impoundments are required to be constructed with two feet of compacted soil with a hydraulic conductivity of no more than 1x10-7

cm/sec, a composite liner that meets the 

requirements of §257.70(b), or an alternative liner that meets the requirements of §257.70(c).

3 This requirement does not apply to an incised CCR surface impoundment.

4

In existing regulations at 40 CFR part 257, subpart A.
Document submitted to conclude E.O.12866 Review

17

8. Severability. EPA intends that the provisions of this rule be severable. In the event that 

any individual provision or part of this rule is invalidated, EPA intends that this would not render 

the entire rule invalid, and that any individual provisions that can continue to operate will be left 

in place.

E. When must owners or operators of CCR landfills and CCR surface impoundments meet 

the minimum national criteria?

The rule becomes effective six months after the publication date of this rule. The final 

rule establishes timeframes for certain technical criteria based on the amount of time determined 

to be necessary to implement the requirements (e.g., installing the groundwater monitoring wells 

and establishing the groundwater monitoring program). In establishing these timeframes, EPA 

accounted for other Agency rulemakings that are anticipated to also affect the owners or 

operators of CCR units, namely the Effluent Limitations Guidelines and Standards for the Steam 

Electric Power Generating Point Source Category (78 FR 34432; proposed rule issued June 7, 

2013) and the Carbon Pollution Emission Guidelines for Existing Stationary Sources: Electric 

Utility Generating Units (79 FR 34830; proposed rule issued June 18, 2014). Specifically, EPA 

developed implementation timeframes that would ensure that owner or operators of CCR units 

would not be required to make decisions about those CCR units without first understanding the 

implications that such decisions would have for meeting the requirements of all applicable EPA 

rules.

F. Deferral of Final Bevill Determination

This rule defers a final Bevill Regulatory Determination with respect to CCR that is

disposed in CCR landfills and CCR surface impoundments until additional information is 

available on a number of key technical and policy questions. This includes information needed 
Document submitted to conclude E.O.12866 Review

18

to quantify the risks of CCR disposal, and the potential impacts of recent Agency regulations on 

the chemical composition of CCR. The Agency also needs further information on adequacy of 

the state programs.

G. Beneficial Use

The final rule retains the Bevill exclusion for CCR that is beneficially used, and provides 

a definition of beneficial use to distinguish between beneficial use and disposal.

H. Implementation

Because the regulations have been promulgated under sections 1008(a), 4004(a), and 

4005(a) of RCRA, the rule does not require permits, does not require states to adopt or 

implement these requirements, and EPA cannot enforce these requirements. Instead, states or 

citizens can enforce the requirements of this rule under RCRA’s citizen suit authority; the states 

can also continue to enforce any state regulation under their independent state enforcement 

authority. (For a more detailed discussion of EPA authorities under RCRA and its relationship to 

this rule, see 75 FR 35128, June 21, 2010). EPA recognizes the significant role states play in 

implementing these requirements and EPA strongly encourages states to revise their Solid Waste 

Management Plans (SWMPs or plans) to show how these new criteria will be implemented. EPA 

would then review and approve the revised SWMPs provided they demonstrate that the 

minimum federal requirements in this final rule will be met. In this way, EPAs approval of a 

revised SWMP signals EPA’s opinion that the State SWMP meets the minimum federal criteria. 

For a more detailed discussion on the role of state solid waste management plans, please refer to 

Section IX.

I. Characterization of Baseline Affected Entities and CCR Management Practices
Document submitted to conclude E.O.12866 Review

19

This action will affect CCR generated by coal-fired electric utility plants in the NAICS 

industry code 221112 (i.e., the ‘‘Fossil Fuel Electric Power Generation’’ industry within the 

NAICS 22 ‘‘Utilities’’ sector code). Based on 2012 electricity generation data published by the 

Energy Information Administration (EIA), the Regulatory Impact Analysis (RIA) for this action 

estimated that a total of 478 operational coal-fired electric utility plants in this NAICS code 

could be affected by this action. These plants are owned by 242 entities consisting of 166 

companies, 17 cooperative organizations, 58 state or local governments, and one federal agency. 

A sub-total of 81 of the 242 owner entities (i.e., 33 percent may be classified as small businesses, 

small organizations, or small governments. The 478 coal-fired electric utility plants operate a 

total of 1,045 CCR management units (735 surface impoundments and 310 landfills). These 478 

plants generate 120.4 million tons of CCR, consisting of 201 plants (42 percent) disposing in onsite landfills, 169 (35 percent) disposing in on-site ponds, and 197 (41 percent) disposing in offsite landfills. Because some plants use more than one CCR management method, these plant 

counts exceed 478 total plants. In addition, 293 of the 478 plants supply CCR for beneficial uses 

in at least 14 industries. Nineteen of the 293 plants solely supply CCR for beneficial uses. As of 

2012, CCR beneficial uses (i.e., industrial applications) involved about 52 million tons annually. 

J. Summary of Estimated Regulatory Costs and Benefits

The EPA estimated future regulatory compliance costs and expected future human health 

and environmental protection benefits in a RIA document which is available from the docket for 

this action. The estimated costs and benefits for the CCR rule are incremental to the baseline 

(current) practices by the electric utility industry to manage CCR in accordance with (a) existing 

state government environmental regulations and (b) utility company CCR management methods. 
Document submitted to conclude E.O.12866 Review

20

The RIA estimates the cost of the rule over a 100 year period because of: (1) CCR 

disposal unit lifespans (40 years to 80 years of age); (2) groundwater migration (estimated time 

to peak potential exposures of CCR through groundwater migration to drinking water wells is 75 

years); and (3) latency periods for onset of illness after exposure to CCR, which can average 20 

years.

Table 1 below summarizes the estimated incremental costs and benefits of the rule. The 

RIA estimates costs to comply with the 12 pollution control requirements associated with the rule, 

as well as estimated monetized values for 11 expected benefits, and discusses 11 other nonmonetized benefits.

Table 1

EPA Estimated Incremental Costs & Benefits of the CCR Rule

(millions 2013$ over 100-year period of analysis 2015-2114)

3% discount rate 7% discount rate

A. Annualized Values

A1. Total Costs $735 $509

A2 Total monetized benefits $289 $232

A3. Net Benefits (A2 - A1) ($446) ($277)

A4. Benefit to Cost Ratio (A3 / A1) 0.39 0.46

B. Present Value

B1. Total Costs $23,200 $7,260

B2 Total monetized benefits $8,550 $3,290

B3. Net Benefits (B2 - B1) ($14,650) ($3,970)

B4. Benefit to Cost Ratio (B2/ B1) 0.37 0.45

II. Statutory Authority 

These regulations are established under the authority of sections 1006(b), 1008(a), 

2002(a), 3001, 4004, and 4005(a) of the Solid Waste Disposal Act of 1970, as amended by the 

Resource Conservation and Recovery Act of 1976 (RCRA), as amended by the Hazardous and 
Document submitted to conclude E.O.12866 Review

21

Solid Waste Amendments of 1984 (HSWA), 42 U.S.C. §§ 6906(b), 6907(a), 6912(a), 6944 and 

6945(a).

RCRA section 1006(b) directs EPA to integrate the provisions of RCRA for purposes of 

administration and enforcement and to avoid duplication, to the maximum extent practicable, 

with the appropriate provisions of other EPA statutes. Section 1006(b) conditions EPA’s 

authority to reduce or eliminate RCRA requirements on the Agency’s ability to demonstrate that 

the integration meets RCRA’s protectiveness mandate (42 U.S.C. 6005(b)(1)). See Chemical 

Waste Management v. EPA, 976 F.2d 2, 23, 25 (D.C. Cir.1992).

RCRA section 1008(a) authorizes EPA to publish “suggested guidelines for solid waste 

management.” 42 U.S.C. 6907(a). RCRA defines solid waste management as “the systematic 

administration of activities which provide for the collection, source separation, storage, 

transportation, transfer, processing, treatment, and disposal of solid waste.” 42 U.S.C. § 

6903(28).

Pursuant to section 1008(a)(3), the guidelines are to include the minimum criteria to be 

used by the states to define the solid waste management practices that constitute the open 

dumping of solid waste or hazardous waste and are prohibited as “open dumping”under section 

4005. Only those requirements promulgated under the authority of section 1008(a)(3) are 

enforceable under section 7002 of RCRA. 

RCRA section 4004 generally requires EPA to promulgate regulations containing criteria 

for determining which facilities shall be classified as sanitary landfills (and therefore not “open 

dumps”). The statute directs that, “at a minimum, the criteria are to ensure that units are 

classified as sanitary landfills only if there is no reasonable probability of adverse effects on 

health or the environment from disposal of solid wastes at such facility.” 42 U.S.C. § 6944(a).
Document submitted to conclude E.O.12866 Review

22

RCRA section 4005(a), entitled “Closing or upgrading of existing open dumps” generally 

establishes the key implementation and enforcement provisions applicable to EPA regulations 

issued under sections 1008(a) and 4004(a). Specifically, this section prohibits any solid waste 

management practices or disposal of solid waste that does not comply with EPA regulations 

issued under RCRA section 1008(a) and 4004(a). 42 U.S.C. § 6944(a). See also 42 U.S.C. § 

6903(14) (definition of “open dump”). This prohibition takes effect “upon promulgation” of any 

rules issued under section 1008(a)(3) and is enforceable through a citizen suit brought pursuant 

to section 7002. As a general matter, this means that facilities must be in compliance with any 

EPA rules issued under this section no later than the effective date of such rules, or be subject to 

a citizen suit for “open dumping” 42 U.S.C. § 6945. RCRA section 4005 also directs that open 

dumps, i.e., facilities out of compliance with EPA’s criteria, must be “closed or upgraded.” 

Section 7004 lays out specific requirements relating to public participation in regulatory 

actions under RCRA. Subsection (b) provides that “[p]ublic participation in the 

...implementation, and enforcement of any regulation under this chapter shall be provided for, 

encouraged, and assisted by the Administrator.” 42 U.S.C. § 6974(b). 

A. Regulation of Solid Wastes under RCRA Subtitle D

Solid wastes that are neither a listed nor characteristic hazardous waste are subject to the 

requirements of RCRA subtitle D. Subtitle D of RCRA establishes a framework for federal, 

state, and local government cooperation in controlling the management of non-hazardous solid 

waste. The federal role is to establish the overall regulatory direction, by providing minimum 

nationwide standards that will protect human health and the environment, and to provide 

technical assistance to states for planning and developing their own environmentally sound waste 

management practices. The actual planning and any direct implementation of solid waste 
Document submitted to conclude E.O.12866 Review

23

programs under RCRA subtitle D, however, remains a state and local function, and the Act 

envisions that states will devise programs to deal with state-specific conditions and needs. EPA 

has no role in the planning and direct implementation of the minimum national criteria or solid 

waste programs under RCRA subtitle D, and has no authority to enforce the criteria. However, 

states are not required to adopt solid waste management programs, and thus, Congress developed 

a statutory structure that creates incentives for states to implement and enforce the federal 

criteria, but that does not necessarily rely on or require a regulatory entity to oversee or 

implement them. While Congress developed the statutory structure to create incentives for states 

to implement and enforce the federal criteria, it does not require them to do so. As a result, 

subtitle D is also structured to be self-implementing.

RCRA sections 1008(a)(3) and 4004(a) delegate broad authority to EPA to establish 

regulations governing the management of solid waste. Under section 4004(a) EPA is charged 

with establishing requirements to ensure that facilities will be classified as sanitary landfills 

“only if there is no reasonable probability of adverse effects on health or the environment from 

the disposal of solid waste” at the facility. Or in other words, under section 4004(a) EPA is 

charged with issuing regulations to address all “reasonable probabilities of adverse effects” (i.e., 

all reasonably anticipated risks) to health and the environment from the disposal of solid waste. 

Section 1008(a)(3) expands EPA’s authority to address the risks from any of the listed activities. 

Specifically, EPA is authorized to establish requirements applicable to “storage, transportation, 

transfer, processing, treatment, and disposal of solid waste.” (42 U.S.C. §§ 6907(a), 6903(28)). 

EPA interprets the standard in section 4004(a) to apply equally to criteria issued under 

sections 1008(a)(3) and 4004(a); namely that the criteria must ensure that a facility is to be 

classified as a sanitary landfill, and thus allowed to continue to operate, “only if there is no 
Document submitted to conclude E.O.12866 Review

24

reasonable probability of adverse effects on health or the environment” from either the disposal 

or other solid waste management practices at the facility. Thus, under the combined authority 

conferred by sections 1008(a)(3) and 4004(a), a facility is an “open dump” if it engages in any 

activity involving the management of solid waste that does not meet the standard in section 

4004(a); or in other words, any activity involved with the management of solid waste that 

presents a reasonable probability of causing adverse effects on health or the environment. EPA 

also interprets these provisions to authorize the establishment of criteria that define the manner in 

which facilities upgrade or close, consistent with the standard in section 4004(a), to ensure there 

will be no reasonable probability of adverse effects on health or the environment.

As discussed previously, Congress created a regulatory structure that limited EPA’s role 

to the creation of national criteria that would operate even in the absence of a regulatory entity to 

oversee or implement the criteria. Under RCRA section 4005(a), upon promulgation of criteria 

under section 1008(a)(3), any solid waste management practice or disposal of solid waste that 

constitutes the ‘‘open dumping’’ of solid waste is prohibited. The federal standards apply 

directly to the facility (are self-implementing) and facilities are directly responsible for ensuring 

that their operations comply with these requirements. States are not required to incorporate or 

implement these requirements under any state permitting program or other state law requirement, 

and EPA is not authorized to impose such requirements, directly or indirectly on the states.

States and citizens may enforce this prohibition (and therefore, the federal criteria) using the 

authority under RCRA section 7002.1

 

1 EPA also may act if the handling, storage, treatment, transportation, or disposal of such wastes may 

present an imminent and substantial endangerment to health or the environment, pursuant to RCRA 

section 7003.
Document submitted to conclude E.O.12866 Review

25

The statute also creates incentives to states to implement the criteria. Chief among the 

incentives is a greater role in implementation and enforcement of the solid waste program, 

including to a limited extent the ability to give facilities that are operating within their state 

additional time to come into compliance with newly promulgated EPA criteria. Specifically, if 

the facility is located in a state with a plan that was approved under section 4003(b), the state

may grant the facility an extension of up to five years from the date the final rule was published 

in the Federal Register to come into compliance with EPA regulations, provided: (a) the facility 

is listed in a state inventory of open dumps; and (b) the facility has demonstrated that it has 

considered other public or private alternatives for solid waste management to comply with the 

prohibition on open dumping and is unable to utilize such alternative. For facilities that meet 

these requirements, the state may establish a “schedule for compliance” which specifies a 

schedule of remedial measures, including an enforceable sequence of actions or operations, 

leading to compliance with the requirements “within a reasonable time (not to exceed five years 

from the date of publication of criteria under section [1008] (a)(3) of this title).” 42 U.S.C. § 

6945(a).

As a consequence of this statutory structure – the requirement to establish national

criteria and the absence of any requirement for direct regulatory oversight—to establish the 

criteria, EPA must demonstrate, through factual evidence available in the rulemaking record, that 

the final rule will achieve the statutory standard (“no reasonable probability of adverse effects on 

health or the environment”) at all sites subject to the standards based exclusively on the final rule 

provisions. This means that the standards must account for and be protective of all sites, 

including those that are highly vulnerable. 

III. Background 
Document submitted to conclude E.O.12866 Review

26

A. EPA’s Proposed Rule

On June 21, 2010 (75 FR 35128), EPA proposed to regulate CCR under RCRA to 

address the risks from the disposal of CCR generated from the combustion of coal at electric 

utilities and independent power producers. As described in the proposal, CCR are residuals 

generated from the combustion of coal and include fly ash, bottom ash, boiler slag (all composed 

predominantly of silica and aluminosilicates), and flue gas desulfurization (FGD) materials 

(predominantly Ca-SOx compounds) and can be managed in either wet (surface impoundments) 

or dry (landfills) disposal systems. EPA noted in the proposed rule that the constituents of most 

environmental concern in CCR are metals, such as antimony, arsenic, barium, beryllium, 

cadmium, chromium, lead, mercury, nickel, selenium, silver and thallium. EPA also presented 

data showing numerous instances where these constituents (especially arsenic) have leached at 

levels of concern from unlined and inadequately clay-lined landfills and surface impoundments. 

In the proposal, EPA revisited its August 1993 and May 2000 Bevill Regulatory 

Determinations regarding CCR generated at electric utilities and independent power producers. 

The results from this effort led the Agency to consider two primary options for the management 

of CCR and thus, propose two alternative regulatory strategies. Under the first option, EPA 

proposed to reverse its August 1993 and May 2000 Bevill Regulatory Determinations (58 FR

42466 and 65 FR 32214 respectively) regarding CCR and to list these residuals as special wastes 

subject to regulation under subtitle C of RCRA when they are destined for disposal in landfills or 

surface impoundments. Under this proposed option, CCR would be regulated from the point of 

generation to the point of final disposition and would generally be subject to the existing subtitle 

C regulations at 40 CFR parts 260 through 268, as well as the permitting requirements in 40 CFR 

Part 270, and the state authorization process in 40 CFR Parts 271-272. Among other things, the 
Document submitted to conclude E.O.12866 Review

27

regulatory requirements included waste characterization, location restrictions, liner and, if 

applicable, leachate collection requirements for land disposal units, fugitive dust controls, 

groundwater monitoring and corrective action requirements, closure and post-closure care 

requirements, financial assurance, permitting requirements, and recordkeeping and reporting 

requirements. This option also imposed requirements on generators and transporters of CCR 

destined for disposal, including manifesting (if the CCR destined for disposal is sent off-site).

However, in light of practical difficulties in implementing certain subtitle C regulatory 

requirements, EPA also proposed to revise selected requirements under the subtitle C option. 

Consequently, EPA proposed, pursuant to its authority under section 3004(x) of RCRA, 

modifications to the CCR landfill and surface impoundment liner and leak detection system

requirements, the effective dates for the land disposal restrictions, and the surface impoundment 

retrofit requirements. EPA also proposed to establish new land disposal prohibitions and 

treatment standards for both wastewater and non-wastewater forms of CCR. In part, the 

proposed modifications to the treatment standards would result in the closure of existing surface 

impoundments and the prohibition of all new surface impoundments. (See 75 FR 35128 for a 

complete discussion of this proposed option).

Under the second option, EPA proposed to retain the August 1993 and May 2000 Bevill 

Regulatory Determinations and to regulate CCR disposal under subtitle D of RCRA by issuing 

national minimum criteria to ensure the safe disposal of CCR in surface impoundments and 

landfills. Under this option, CCR would remain classified as a non-hazardous RCRA solid waste.

EPA proposed to establish technical requirements, many of which were nearly identical to the 

technical standards proposed under the subtitle C option. The technical standards included, 

among other things, locations standards, liner and leachate collection requirements, groundwater 
Document submitted to conclude E.O.12866 Review

28

monitoring and corrective action standards for releases from the units, operating criteria, such as 

fugitive dust control, closure and post-closure care requirements, and recordkeeping and 

reporting requirements. Under this option, EPA did not propose to establish regulatory 

requirements that would restrict the generation, transportation, storage, or treatment of CCR 

prior to disposal, nor did EPA propose to establish financial assurance requirements under 

RCRA.2 Also, because of subtitle D’s limitations, the proposed rule did not require permits; nor 

could EPA enforce the national minimum criteria. Rather, states or citizens could enforce the 

national minimum criteria under RCRA’s citizen suit authority, and states could continue to 

enforce any state regulation that applies to CCR under their independent state enforcement 

authority.

The subtitle D proposed option was designed to be self-implementing, meaning that the 

requirements were such that facilities could comply with the regulatory requirements without the 

need to interact with a regulatory authority. EPA sought to enhance the protectiveness of the 

proposed option by requiring certified demonstrations by an independent registered professional 

engineer to provide verification that the regulatory requirements were being adhered to. In 

addition, the option provided for state and public notification of the certifications, as well as 

 

2

In the proposal, the Agency stated that the RCRA subtitle D alternative did not include proposed 

financial responsibility requirements and that any such requirements would be proposed separately. The 

Agency solicited comment on whether financial responsibility requirements under CERCLA section 

108(b) should be a key Agency focus under a RCRA subtitle D approach. While the Agency received 

numerous comments urging the Agency to establish financial responsibility as part of the subtitle D 

option, the CERCLA 108(b) option did not receive significant support. As discussed in the proposal and 

reiterated here, EPA will not be requiring financial assurance requirements as part of this rule. The 

Agency however will continue to investigate the use of other statutory authorities (e.g., CERCLA) to 

establish financial responsibility requirements for owners or operators of CCR landfills, CCR surface 

impoundments and any lateral expansion. 
Document submitted to conclude E.O.12866 Review

29

required posting of certain information on a website maintained by the facility and in the 

operating record. (See 75 FR 35128 for a complete discussion of this proposed option).3

The Agency also described other alternatives considered. For example, one subtitle D 

option, called “D-prime” was structured so that all existing CCR surface impoundments could 

continue to receive CCR after the effective date of the rule for the remainder of the unit’s useful 

life, irrespective of their liner type, provided the other provisions of the subtitle D option were 

met (e.g., groundwater monitoring). (See 75 FR 35128 for a complete discussion of this and 

other possible regulatory alternatives on which the Agency solicited comment.) 

Under both the subtitle C and subtitle D alternatives, EPA proposed establishing dam 

safety requirements to address the structural integrity of surface impoundments. EPA also 

proposed not to change the May 2000 Regulatory Determination for beneficially used CCR, 

which are currently exempt from the hazardous waste regulations under section 3001(b)(3)(A) of 

RCRA. EPA also did not propose to address the placement of CCR in mines, or non-minefill 

uses of CCR at coal mine sites.

In addition to proposing these two regulatory options for the management of CCR, EPA 

identified many issues on which it solicited comment, information, and data. Certain solicitations 

were very general, such as comments on alternative options for regulating CCR, while other 

requests for comment were very specific in nature, for example, whether clay liners designed to 

meet a specified hydraulic conductivity might perform differently in practices than modeled in 

the risk assessment. (The Agency requested comment on issues throughout the preamble;

 

3 While EPA cannot enforce the subtitle D proposed rules, EPA can take action under section 7003 of 

RCRA to abate conditions that “may present an imminent and substantial endangerment to health or the 

environment.” EPA can also use the imminent and substantial endangerment authorities under the 

CERCLA, or under other federal authorities to address those circumstances where a unit(s) may pose a 

threat. 
Document submitted to conclude E.O.12866 Review

30

however specific issues for which EPA solicited comment can be found at 75 FR 35221-34224.)

B. Comments Received on the Proposed Rule 

The Agency received over 450,000 comments on the proposed rule. The majority of the 

commenters focused on which regulatory path the Agency should pursue for regulating CCR, 

i.e., RCRA’s subtitle C or subtitle D. A number of commenters, however, argued that no 

additional regulation was necessary and that the states were adequately regulating the 

management of CCR. Generally, environmental groups and individual citizens favored a subtitle 

C rule arguing that state programs have failed and damage cases are growing in number. State 

organizations, individual states, and industry groups (electric utilities, recycling firms, trade 

associations), largely favored a subtitle D rule with a permitting program. 

One area that received extensive comment was the re-evaluation of the eight Bevill study 

factors.4 Numerous commenters provided detailed analysis related to the study factors and 

provided their own interpretations of the data (e.g., state programs and damage cases). Other 

areas that received significant comment included beneficial use and the risk assessment.

Discussions of the specific comments germane to this rulemaking are provided in the 

relevant sections of this notice.

 

4

 In considering whether to retain or to reverse the August 1993 and May 2000 Regulatory 

Determinations regarding the Bevill exemption of CCR destined for disposal, the Agency re-examined the 

RCRA section 8002(n) study factors. These eight study factors are: (1) source and volumes of CCR 

generated per year; (2) present disposal and utilization practices (which includes evaluation of existing 

state regulatory oversight and beneficial use); (3) potential danger, if any, to human health and the 

environment from the disposal and reuse of CCR; (4) documented cases in which danger to human health 

or the environment from surface runoff or leachate has been proved; (5) alternatives to current disposal 

methods; (6) the cost of such alternative disposal methods; (7) the impact of the alternative disposal 

methods on the use of coal and other natural resources; and (8) the current and potential utilization of 

CCR (see 75 FR 35128).
Document submitted to conclude E.O.12866 Review

31

C. Other Actions During Which Comment Was Taken

1. Public Hearings

EPA conducted eight public hearings during the months of August, September, and 

October in 2010. There were over 1300 individual speakers at the eight public hearings that 

commented on the proposed rule. Testimony at the public hearings focused generally on whether 

EPA should adopt a subtitle C or subtitle D approach for regulating CCR. Many commenters 

were also concerned with fugitive dust emissions and the effect these emissions had on their 

health and overall well-being. Other commenters were concerned that adopting a subtitle C rule 

for CCR would negatively affect the beneficial use of the material. In addition to their 

testimonies that were entered into the rulemaking record, over 1200 additional documents were 

submitted in hard copy and entered into the docket (see EPA-HQ-RCRA-2009-0640).

2. Notices of Data Availability 

Subsequent to the proposed rule, the Agency published several Notices of Data 

Availability (NODAs), the first on October 21, 2010, (75 FR 64974); the second on October 12, 

2011 (76 FR 63252) and the third on August 2, 2013 (78 FR 46940). Specifically:

• The first NODA invited comment on the responses EPA received on Information 

Collection Requests that were sent to electric utilities on their CCR surface 

impoundments, as well as reports and materials related to the site assessments EPA had 

conducted on a subset of these impoundments. 

• The second NODA invited comment on a number of topics, including (1) chemical 

constituent data from coal combustion residuals; (2) facility and waste management unit 

data; (3) information on additional alleged damage cases; (4) the adequacy of state 

programs; and (5) beneficial use. 
Document submitted to conclude E.O.12866 Review

32

• The third NODA invited comment on (1) supplemental data for the risk assessment; (2) 

supplemental data for the RIA; (3) information regarding large-scale fill; and (4) data on 

the CCR Impoundment Assessment Program. EPA also sought comment on two technical 

issues associated with the requirements for CCR management units: closure requirements 

and regulation of overfills (i.e., CCR management units built directly over pre-existing 

CCR landfills or CCR surface impoundments).

Specific comments received on each of the three NODAs are discussed in the relevant 

sections of this rule.

3. Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating 

Point Source Category Proposed Rule

On June 7, 2013 (78 FR 34432), EPA proposed a regulation that would strengthen the 

controls on discharges from certain steam electric power plants by revising the technology-based 

effluent limitation guidelines (ELG) and standards for the steam electric power generating point 

source category. As part of this proposal, EPA discussed its current thinking on how a final 

RCRA CCR rule might be aligned and structured to account for any final requirements adopted 

under the ELG for the Steam Electric Power Generating point source category. Two primary 

means of integrating the two rules were discussed: (1) coordinating the design of any final 

substantive CCR regulatory requirements and (2) coordinating the timing and implementation of 

the rules to allow facilities to coordinate their compliance planning and implementation and to 

protect electricity reliability for consumers. EPA stated that consistent with RCRA section 

1006(b), effective coordination of any final RCRA requirements with the ELG requirements 

would be sought in order to minimize the overall complexity of the two regulatory structures, 

and facilitate implementation of engineering, financial, and permitting activities. EPA solicited 
Document submitted to conclude E.O.12866 Review

33

comments on how any final CCR final rule might be aligned and structured to account for any 

final requirements adopted under the ELG for the Steam Electric Power Generation point source 

category.

D. EPA’s CCR Impoundment Assessment Program

In March 2009, the Agency’s CCR Impoundment Assessment Program (herein referred 

to as the Assessment Program) was initiated. This effort was in response to the December 22, 

2008 dike failure of a coal ash impoundment at the Tennessee Valley Authority (TVA) Kingston 

Fossil Plant in Harriman, Tennessee where over one billion gallons of coal ash slurry were 

released, affecting more than 300 acres, including residences and infrastructure. The TVA 

Kingston impoundment failure ignited a nation-wide concern over the safety of coal ash 

impoundments; and EPA was tasked with determining whether the potential existed for similar 

impoundment failures at other coal-fired power plants. In response, EPA developed the 

Assessment Program to evaluate the structural stability and safety of all coal ash impoundments 

throughout the country.5 As of September 2014, 559 impoundments had been assessed at over 

230 coal-fired power plants. 

The Assessment Program began as a separate effort from the development of this final 

rule.6 However, the information and experience developed in carrying out the site assessments 

during the Assessment Program is directly relevant to many of the issues addressed in this 

rulemaking, and provide further technical support for many of the technical criteria. 

 

5 The focus of the Assessment Program was to assess the structural integrity of CCR impoundments 

meeting specified criteria. The Agency did not include, as part of its evaluation, the assessment of other 

conditions/characteristics of the impoundment that may present potential risks to human health or the 

environment, i.e., groundwater contamination due to an insufficient liner design. 

6 EPA issued two Notices of Data Availability (75 FR 35128 (October 21, 2101) and 78 FR 46940 

(August 2. 2013)) specifically soliciting comment on the information generated by the Assessment 

Program and the materials posted on our website. 
Document submitted to conclude E.O.12866 Review

34

Consequently, many of the final technical criteria were developed in direct response to findings 

from the site assessments. For example, several of the technical criteria contained in the 

proposed rule were modified to account for the widely accepted engineering methodologies and 

practices used in conducting the site assessments, as well as current facility practices 

documented during the assessments. In a few instances, the criteria were supplemented to better 

align the technical requirements with the Assessment Program. Included among the final criteria 

that directly rely on the Assessment Program are the provisions relating to structural integrity 

assessments to address factors of safety, periodic reassessments, hazard potential classifications, 

and the hydrologic and hydraulic capacity of CCR surface impoundments. These requirements 

are further discussed in Unit VI of this preamble.

The Assessment Program focused on impoundments meeting four general criteria that 

were designed to identify the units most likely to present the same risks as the collapsed TVA 

impoundment: (1) above ground or diked; (2) of sufficient height to be susceptible to structural 

failure (i.e., six feet); (3) receiving CCR; and (4) located at operating coal-fired power plants 

selling power to the electric grid. Also included in the assessments were a number of inactive 

impoundments, i.e., impoundments not receiving CCR but still containing CCR and/or liquid. 

The Agency included these inactive units in the assessment reasoning that these units would be 

as susceptible to structural failure as units currently receiving CCR, given that they still 

contained CCR and maintained an ability to impound water (i.e., the unit had not been breached). 

The Assessment Program did not evaluate, however, incised (not having above ground berms or 

dikes) impoundments or landfills (not containing liquid slurried CCR wastes). EPA chose not to 

assess these units because they did not share the characteristics of impoundments likely to raise 
Document submitted to conclude E.O.12866 Review

35

concern for catastrophic releases, and because no known catastrophic structural failures were 

associated with these types of units. 

Prior to initiating the assessments, EPA consulted with two key dam safety organizations, 

the Association of State Dam Safety Officials (ASDSO) and the Mine Safety and Health 

Administration (MSHA) to better understand how these federal and state dam inspection 

programs operated, including how earthen dams and impoundments were assessed.

7 These 

groups provided the Agency with critical insight and information for inspecting and evaluating 

CCR impoundments. The Agency also reviewed various technical documents relating to dam 

safety and conducting impoundment inspections, many of which were recommended by these 

organizations. These were: (1) U.S. Army Corp of Engineers (USACE) 2008 National Inventory 

of Dams (NIDS); (2) FEMA’s Federal Guidelines for Dam Safety - Hazard Potential 

Classification System for Dams (April 2004); (3) FEMA’s Risk Prioritization Tool for Dams 

User Manual (March 2008); (4) MSHA’s Handbook (PH07-01); (5) MSHA’s Coal Mine 

Impoundment Inspection and Plan Review Handbook (October 2007); and (6) MSHA’s 

Engineering and Design Manual: Coal Refuse Disposal Facility (May 2009); (7) ASDSO’s 

“Summary of State Dam Safety Laws and Regulations,” (2000); (8) ASDSO’s “Owner 

Responsible Periodic Inspection Guidance,” (2005); (9) “Guidelines for Inspections of Existing 

Dams.” New Jersey Department of Environmental Protection – Dam Safety (January 2008). 

In developing the criteria that were used to conduct the assessments, a standard rating 

system was developed to classify the units’ suitability for continued safe and reliable operation. 

 

7 ASDSO identified for EPA key documents to review including Federal Energy Regulatory Commission 

(FERC) and Mine Safety and Health Administration (MSHA) guidance.
Document submitted to conclude E.O.12866 Review

36

EPA modeled its impoundment condition rating criteria on those developed by the State of New 

Jersey (see reference above). 

1. Conducting the Site Assessments 

In order to prioritize the assessments, a preliminary hazard potential classification 

ranking was identified for each impoundment, based on criteria developed by the Federal 

Emergency Management Agency (FEMA) and found generally in US Army Corps of Engineers’

(USACE) National Inventory of Dams (NID). EPA elected to evaluate first those impoundments 

with a high hazard potential classification, which signifies that a failure or mis-operation of the 

unit would probably result in the loss of human life. 

Upon initiation of the Assessment Program, every owner or operator of a CCR 

impoundment was contacted by the Agency and supplied with information on the objectives of 

the assessment and how the assessments were to be conducted. Assessments were conducted in 

rounds, consisting of groups of 12-26 facilities per round.8 Prior to each site assessment, to 

ensure uniformity throughout the study, a statement of work and an impoundment field checklist 

was developed and adhered to during the assessment. 

To ensure objectivity, EPA contracted with professional engineers (PEs) in the state 

where the impoundment was located who were experts in the area of dam safety to perform the 

site assessments. Each individual assessment was performed by professional engineers qualified 

in the areas of geotechnical engineering, hydrology and hydraulics, and overall dam safety. 

Upon evaluation of a robust set of technical documents addressing dam safety and inspections as 

well as comprehensive discussions with key dam safety organizations, the Assessment Program 

 

8 The results of this effort are either presented on a facility by facility basis or are summarized by round. 

All of these data have been posted on the Agency website.
Document submitted to conclude E.O.12866 Review

37

developed a comprehensive set of factors that were to be used to evaluate the overall safety of 

CCR surface impoundments, which concluded that, among other important factors, the static and 

seismic factors of safety, hydrologic and hydraulic capacity, liquefaction potential analysis and a 

post-liquefaction stability analysis if the soils of the embankment were identified to be 

susceptible to liquefaction , and operation and maintenance protocols, e.g. instrumentation 

monitoring, inspection program, emergency response protocols were critical parameters for 

assessing the overall safety of CCR surface impoundments. 

The individual evaluations or assessments were conducted at each impoundment at each 

facility using standard, accepted engineering practices, including a visual assessment of the CCR 

surface impoundment, interviews with site personnel, a review of the history of the CCR surface 

impoundment, and a review of engineering documentation related to the design, construction, 

operation, and maintenance of the impoundments, including available technical analyses. At 

each site visit, additional documentation was collected and reviewed as available, including 

descriptions, along with supporting information, of: (1) the impoundment, including location, 

size, age, design and/or alterations to the design, and the amount of residuals currently in the 

unit; (2) known, measured settlement of the impoundment embankment; (3) known, measured 

movement of the impoundment embankment; (4) observed erosion of the impoundment 

embankment; (5) seepage; (6) leakage; (7); observed cracking of the impoundment embankment; 

(8) deterioration, such as scarps, boils, or sloughs, of the impoundment embankment; (9); 

seismicity; (10) internal stresses; (11) functioning of foundation drains and relief wells; (12) 
Document submitted to conclude E.O.12866 Review

38

stability of critical slopes adjacent to the units; and (13) regional and site geological conditions. 

If available, state and federal inspections reports were also reviewed.9 

In addition, for each assessment, the following factors were identified, to the extent 

feasible, for evaluation: (1) the presence and adequacy of spillways; (2) hydrologic and hydraulic 

capacity of the unit; (3) overall structural adequacy and stability of structures under all credible 

loading conditions through a review of static, seismic, and liquefaction analyses with determined 

factors of safety; (4) soil, groundwater, surface water, geology, and geohydrology characteristics 

associated with the unit, including hydrological data accumulated since the impoundment was 

constructed or last inspected; (5) a history of the performance of the management unit through 

analysis of data from monitoring instruments, interviews with facility personnel, and review of 

available operating records; (6) quality and adequacy of maintenance, surveillance, and methods 

of unit operations for the protection of public safety; (7) location of schools, hospitals, or other 

critical infrastructures within five miles down gradient of the impoundment and (8) whether the 

impoundment is located within federally designated flood plains. Finally, each impoundment 

and any associated spillways were evaluated to determine whether the impoundment and the 

spillways could withstand the loading or overtopping from appropriate inflow design flood 

events. 

Each CCR surface impoundment was classified with a Hazard Potential Classification 

following State of New Jersey Department of Environmental Protection Bureau of Dam Safety 

and Flood Control hazard potential ranking. Each impoundment was classified with a hazard 

potential classification of either; “High,” “Significant,” “Low,” or “Less-than-Low.” The hazard 

 

9

It is important to note that during the assessment, no physical drilling, coring or sampling was 

conducted, while on site; however, studies were reviewed that often included such information.
Document submitted to conclude E.O.12866 Review

39

potential classification was a qualitative assessment of the potential adverse incremental 

consequences of a dam failure. 

At the conclusion of each assessment, a report was generated and the impoundment was 

given a condition rating of either; “satisfactory,” “fair,” “poor,” or “unsatisfactory.” The 

condition ratings were based on the availability of information on the unit and evaluation of the 

previously mentioned factors, including the static, seismic, and liquefaction factors of safety. No 

impoundments received an “unsatisfactory” rating. Numerous impoundments were, however,

rated as “poor,” often for lack of appropriate technical documentation in the aforementioned 

areas. “Poor” or “fair” ratings were also an indication that additional measures were needed to 

improve the stability of the unit. Of 559 impoundments assessed, 241 received a condition rating 

of “satisfactory,” 166 received a condition rating of “fair,” and 152 received a “poor” condition 

rating. 

It is important to note that the condition rating did not necessarily imply that the unit had 

inadequate structural integrity. On the contrary, in many instances a structurally sound 

impoundment may have been given a condition rating or “fair” or “poor” based on other factors 

such as a lack of documented information on the unit or insufficient operations and maintenance 

protocols. For example, an impoundment could be rated as “poor” if it lacked the appropriate 

technical documentation and analyses regarding structural or hydrologic and hydraulic analyses.

EPA rated numerous units as “poor” based primarily on unavailable technical analyses. 
Document submitted to conclude E.O.12866 Review

40

Once the assessment was performed, a draft report was prepared. Draft reports were 

reviewed by the appropriate state agency, the utility, and by EPA.10 Once comments were 

received and incorporated, a final report was issued along with recommendations for additional 

actions to be taken by the facility (if needed). Facilities then developed action plans and 

schedules to implement the recommendations. EPA also informed facility owners and operators 

that in addition to implementing their action plans, they need to adopt an ongoing, routine 

program to assess each surface impoundment and to take necessary corrective measures to 

ensure the units’ continued structural integrity. 

2. Assessment Program Findings 

Upon completion of the Assessment Program, a review was undertaken to ascertain the 

key findings or lessons learned from the effort. These key findings included: (1) the owners or 

operators of the majority of CCR surface impoundments currently conduct some form of 

periodic inspection; (2) most utilities were readily able to supplement outdated or missing 

information with new or updated evaluations of their impoundments after the on-site portion of 

EPA’s assessment was conducted; (3) in response to the assessment report recommendations, 

facilities typically willingly conducted remedial actions; (4) interaction with the states and the 

utilities assured accuracy in the final assessment reports; (5) placing site assessment materials on 

an internet site assured that the public, states, and utilities had full access to information about 

the design and operation of CCR impoundments and did not present either homeland security or 

 

10 As noted many times in this notice, states play a critical role in implementing and overseeing 

these units. To assist states in this effort, EPA has, in the majority of cases directly provided the 

states with all of the information from our assessments. The Assessment Program reports may 

be accessed at: http://www.epa.gov/wastes/nonhaz/industrial/special/fossil/surveys2/index.htm 
Document submitted to conclude E.O.12866 Review

41

other confidentiality concerns; (6) static, seismic, and liquefaction analyses did not pose a 

significant technical or cost burden on facilities since many already routinely conducted these 

types of evaluations; (7) state regulatory bodies viewed the assessments as a means to further 

support existing assessment programs; and (8) the use of PEs to certify all final reports ensured 

that the assessments reflected the PE’s best judgments.

3. Assessment Program’s Support for the Structural Integrity Requirements of the Rule

As noted, the findings from EPA’s Assessment Program provide technical and factual 

support for many of the final requirements for structural stability in this rule. A more detailed 

discussion of several of the most significant of these is presented below. Additional discussion of 

the relevance of these findings is included throughout Unit VI.

a. Periodic Inspections

Consistent with the findings from the assessments and with EPA’s recommendations to 

facilities as part of the Assessment Program, this rule requires that all CCR surface 

impoundments be inspected at intervals not exceeding seven days for any appearances of actual 

or potential structural weakness and other conditions that are disrupting or have the potential to 

disrupt the operation or safety of the CCR surface impoundment. Monitoring of instrumentation 

is also required to be conducted at intervals not exceeding 30 days. The Assessment Program 

found that virtually all utility companies conduct some sort of periodic inspection or monitoring 

at CCR surface impoundments, although practices varied among facilities and between states. 

The Assessment Program also found that while many facilities were conducting regularly 

scheduled inspections, some did not adequately document the results of these inspections. 

CCR surface impoundments exceeding a specified size threshold, i.e., height of five feet 

or more and capacity of 20 acre-feet or more or a height of 20 feet or more, are required to 
Document submitted to conclude E.O.12866 Review

42

perform annual inspections as well as three assessments of structural stability quinquennially, 

(i.e., every five years) that include a structural stability assessment of specified parameters, a 

factor of safety assessment, and a hazard potential assessment. Annual inspections are broader in 

scope than weekly inspections and are conducted to ensure that the design, construction, 

operation and maintenance of the CCR unit is consistent with recognized and generally accepted 

good engineering standards. Annual inspections must include a review of available information 

regarding the status and condition of the unit and a visual inspection to identify signs of distress 

or malfunction of the unit and appurtenant structures. The annual inspections must be conducted 

by a qualified professional engineer.

The Assessment Program also reviewed how detailed structural stability reviews and 

inspections were recommended to be conducted by FEMA, MSHA, and the USACE guidelines

and found that such inspections were recommended to take place every three to five years. 

Review of state dam safety programs demonstrated that similar detailed inspections were also 

conducted on a three-to-five year cycle. Therefore, in the final rule, EPA is requiring that 

structural integrity assessments, including the calculation of factors of safety under various 

loading conditions, be conducted within six months of publication of the rule, and be repeated

every five years. The five year review timeframe is based on documentation showing that the 

factual bases for such reviews are only sound for that time period, and is consistent with federal 

dam safety guidance, specifically FEMA. FEMA recommends in Federal Guidelines for Dam 

Safety that dams be formally assessed at a frequency not to exceed five years by a qualified 

professional engineer. EPA has adopted this timeframe to maintain consistency with FEMA 

guidance. The inspection and assessment requirements in this rule will ensure that there are 

consistent and uniform inspection and assessment practices across states and facilities and will 
Document submitted to conclude E.O.12866 Review

43

ensure that problems related to their stability will be promptly identified and remediated as 

necessary. 

b. Static, Seismic, and Liquefaction Factors of Safety 

(1) Static Factors of Safety. 

Factor of safety (FOS) means the ratio of the forces tending to resist the failure of a 

structure, as compared to the forces tending to cause such failure as determined by accepted 

engineering practice. This analysis is used to determine whether a CCR surface impoundment’s 

dikes are engineered to withstand the specific loading conditions that can be reasonably 

anticipated to occur during the lifetime of the unit without failure of the dike, if accepted good 

engineering practices are employed. Static factors of safety refer to the factors of safety (FOS) 

under static loading conditions that can reasonably be anticipated to occur during the lifetime of 

the unit. Static loading conditions are unique from other loading conditions (e.g., seismic, 

liquefaction) in that static loading conditions are those which are in equilibrium, meaning the 

load is at rest or is applied with constant velocity. 

EPA reviewed a series of USACE guidance documents addressing how to determine static 

FOS. These documents included, but were not limited to, Engineer Manual EM 1110-2-

1902“Slope Stability” (October 2003), and EM 1110-2-1902 “Stability of Earth and Rock-Fill 

Dams.” The Agency also assessed the recommendations on how to conduct static analysis 

contained in the Engineering and Design Manual for Coal Refuse Disposal Facilities, originally 

published by the Mining Enforcement and Safety Administration (MESA) in 1975 and updated 

for MSHA in May 2009, and in particular Chapter 6, “Geotechnical Exploration, Material 

Testing, Engineering Analysis and Design.” Based on recommendations from ASDSO, among 

others, the Agency adopted the USACE guidance to determine static FOS, both in the 
Document submitted to conclude E.O.12866 Review

44

Assessment Program and in this rulemaking, as these manuals are recognized throughout 

industry as the standard routinely used in field assessment of structural integrity. 

In EPA’s Assessment Program all CCR units were assessed to determine their static FOS. 

Each assessment classified a CCR unit as having sufficient structural stability under static 

loading conditions if analysis of critical sections of embankments demonstrated FOS that met or 

exceeded the values defined by USACE for static specific loading conditions. EPA found that 

most CCR surface impoundments exhibited sufficient calculated factors of safety under static 

loading conditions. EPA found that in those CCR units which insufficient factors of safety 

against failure due to static loading were calculated, the owner or operator was able to implement 

actions which increased the factors of safety under static loading conditions to acceptable levels. 

Oftentimes, these implemented actions were of a simple nature, such as installing riprap (rock 

armoring the slopes) or buttressing the slopes.

Similarly, this rule adopts the static factors of safety from USACE Engineer Manual EM 

1110-2-1902 “Slope Stability,” with the exception of the rapid drawdown loading condition,11

which was determined not to be relevant to CCR surface impoundments. EPA found the factors 

 

11 Rapid (or sudden) drawdown is a condition in earthen dikes that may develop when the embankment 

becomes saturated through seepage during a high pool elevation in the reservoir. Rapid drawdown 

becomes a threat to the dike when the reservoir pool is drawn down or lowered at a rate significantly 

higher than the excess poor water pressure within the dike can dissipate. Typically, rapid drawdown 

scenarios are considered for dikes with reservoirs used for water supply and management or agricultural 

supply. In these scenarios, a high pool elevation is maintained in the reservoir in storage months. 

Subsequently, the water supply is drawn on in months where there is a demand for the reservoirs contents. 

This drawing down of the pool can present issues for the structural integrity of the unit. However, the 

management of CCR surface impoundments differs from that of conventional water supply reservoirs. 

CCR surface impoundments are never used for water supply, and the only instance in which EPA 

determined through its Assessment Program that rapid drawdown loading conditions would be relevant 

to CCR surface impoundments was in the event that the CCR surface impoundment had already released 

the contents of the impoundment through a breach of the dike or emergency discharge. Since the threat of 

release of CCR and the reservoir has already been realized, any failure due to rapid drawdown of the 

embankment is no longer critical to the overall containment of the now-released contents of the CCR unit.
Document submitted to conclude E.O.12866 Review

45

of safety identified by EM 1110-2-1902, specifically the Maximum Storage pool, Maximum 

Surcharge pool, and End-Of-Construction loading conditions, provided consistent, achievable 

levels of safety in CCR surface impoundment dikes, comprehensively assessed static stability, 

and provided sufficient consideration of compounding stresses on dikes (e.g., factors of safety 

values greater than 1.00 to account for unanticipated loadings acting in conjunction or 

misidentified strength of materials). 

(2) Seismic Factor of Safety. 

Seismic FOS means the FOS determined using analysis under earthquake conditions for a 

seismic loading event, based on the U.S. Geological Survey (USGS) seismic hazard maps for 

seismic events with a specified return period for the location where the CCR surface 

impoundment is located. The seismic FOS analysis is used to determine whether a dam would 

remain stable during an earthquake or other seismic event. The Agency relied on two sources to 

evaluate the appropriate methods to determine if a dam would remain stable during a seismic 

event. This includes the USACE guidance Engineer Circular 1110-2-6061: Safety of DamsPolicy and Procedures 2204, Engineer Circular 1110-2-6000: Selection of Design Earthquakes 

and Associated Ground Motions 2008, and Engineer Circular 1110-2-6001: Dynamic Stability of 

Embankment Dams 2004). EPA also reviewed MSHA’s 2009 Engineering and Design Manual 

for Coal Refuse Disposal Facilities, in particular Chapter 7, “Seismic Design: Stability and 

Deformation Analyses.” These documents are viewed by ASDSO, FEMA and MSHA as 

generally accepted guidance on how to conduct seismic stability analyses.

As noted earlier, in performing the assessments, EPA directed its engineering contractors 

to assess seismic stability of CCR impoundments during and following a seismic event with 2 

Percent Probability of Exceedance in 50 years (i.e. probable earthquake within approximately
Document submitted to conclude E.O.12866 Review

46

2,500 years) and a Horizontal Spectral Response Acceleration for 1.0-Second Period (5 Percent 

of Critical Damping). EPA selected this return period for determining the Maximum Design 

Earthquake (MDE) by first considering the operating life anticipated for CCR surface 

impoundments. EPA has identified the operating life of CCR surface impoundments to range 

between 40-80 years. EPA then consulted the United States Geological Survey and ASDSO to 

determine a conservative probability that should be used in the assessments.12 To reduce the 

likelihood of a CCR unit failing during a seismic event, the Agency assessed various return

periods and chose a conservative 2500 year return period. The use of this “return” period was 

chosen because it is conservative, reflects the fact that many CCR impoundments are located in 

active seismic zones, and the use of a conservative “return” period ensures that if a unit meets the 

seismic FOS it is unlikely to fail under most seismic events. By evaluating seismic stability 

under a conservative return period and requiring the unit to maintain structural stability under 

that design seismic event, the likelihood of a seismic event occurring at the location of the CCR 

surface impoundment in which the strength of the unit is exceeded and the unit fails is 

considerably diminished. Additionally, the unit can reasonably be anticipated to withstand 

seismic events of a more frequent return period (i.e., smaller magnitude). 

The Agency assessed CCR impoundments and classified them as having seismic stability 

if modeling results of critical failure surfaces were calculated to have FOS greater than 1.0 under 

the specified seismic loading condition. The Assessment Program found that most CCR 

impoundments did meet the required seismic FOS. This rule also adopts this seismic stability 

FOS under the 2% probability of exceedance in 50 years event. 

 

12 Wieland, M., “Seismic Design and Performance Criteria for Large Storage Dams”, Proc. 15th World 

Conf. on Earthquake Engineering, Lisbon, Portugal, Sep. 24-28, 2012.
Document submitted to conclude E.O.12866 Review

47

The Assessment Program found that many CCR impoundments had not undergone static 

or seismic analyses in sufficient detail that an independent professional engineer could assert that 

they were stable. The assessments gave impoundments a condition rating of “poor” if the utility 

was unable to provide static and seismic studies of their units conducted in a fashion which 

represented acceptable professional engineering practice. As the Assessment Program advanced, 

many utilities independently conducted new or updated static and seismic analyses of CCR 

surface impoundments in anticipation of their facilities being assessed. By the end of the 

program, virtually all facilities had conducted or were in the process of conducting static and 

seismic analyses. While some utilities noted concern over the costs of conducting additional 

static or seismic stability studies, none found that completing these studies presented any 

significant engineering challenges. 

(3) Liquefaction Factors of Safety.

Liquefaction FOS means the factor of safety determined using analysis under liquefaction 

conditions. Liquefaction is a phenomenon which typically occurs in loose, saturated or partiallysaturated soils in which the effective stress of the soils reduces to zero, corresponding to a total 

loss of shear strength of the soil. The most common occurrence of liquefaction is in loose soils, 

typically sands. The liquefaction FOS determination in the final rule is used to determine if a 

CCR unit would remain stable if the soils of the embankment of the CCR unit were to experience 

liquefaction. EPA relied primarily on one source to evaluate the appropriate methods to 

determine if a dam would remain stable under liquefaction conditions. This source was “Soil 

Liquefaction during Earthquakes,” Idriss and Boulanger, Earthquake Engineering Research 
Document submitted to conclude E.O.12866 Review

48

Institute, 200813. EPA also reviewed several technical resources regarding soil liquefaction, 

including “Ground Motions and Soil Liquefaction During Earthquakes,” Seed and Idriss, 1982,14

“Liquefaction Resistance of Soils: Summary report from the 1996 and 1998 NCEER/NSF 

Workshops on Evaluation of Liquefaction Resistance of Soils,” Youd and Idriss, 2001,15 and 

Seismic Design Guidance for Municipal Solid Waste Landfill Facilities, US EPA, Office of 

Research and Development, 1995.16 These documents are viewed as generally accepted guidance 

on how to conduct liquefaction potential analyses and residual strength analyses under postliquefaction conditions. 

As noted earlier, in performing the assessments, EPA directed its engineering contractors 

to assess the liquefaction potential of soils which compose the embankments of the CCR unit to 

determine if the soils present in the embankment were of the soil classification and configuration 

that was susceptible to liquefaction. This determination was based on evidence available through 

interviews with facility personnel, construction documentation, or representative soil sampling, 

such as information provided by corings and borings. Identical to the requirements for seismic 

factor of safety calculation, EPA selected a return period for a seismic event for analysis of 

liquefaction potential, under a seismic loading which may induce liquefaction in embankments, 

of a 2% probability of exceedance in 50 years. The discussion of the selection of this return 

period can be found in the “Seismic Factor of Safety” section above.

 

13 https://www.eeri.org/products-page/monographs/soil-liquefaction-during-earthquakes-3/

14 Seed, H. B., and Idriss, I. M., 1982, "Ground Motions and Soil Liquefaction During Earthquakes,"

Monograph No. 5, Earthquake Engineering Research Institute, Berkeley, California, pp. 134.

15 Youd, T. L., Idriss, I. M., 2001, “Liquefaction Resistance of Soils: Summary report from the 1996 and

1998 NCEER/NSF Workshops on Evaluation of Liquefaction Resistance of Soils.” Journal of

Geotechnical and Geoenvironmental Engineering, ASCE.

16 United States EPA, Office of Research and Development, 1995, EPA/600/R-95/051, RCRA Subtitle D

(258) Seismic Design Guidance for Municipal Solid Waste Landfill Facilities. Available as of the Writing 

of this policy at www.epa.gov/clhtml/pubtitle.html on the U.S. EPA website.
Document submitted to conclude E.O.12866 Review

49

The Agency assessed CCR impoundments and classified them as having stability under 

liquefaction conditions if representative soil sampling, anecdotal evidence from interviews with 

facility personnel, or construction documentation indicated that there was no susceptibility to 

liquefaction of the embankment soils or if modeling or analysis in critical failure planes in the 

embankment expected to be susceptible to liquefaction were calculated to have a FOS greater 

than 1.00 under post-liquefaction conditions. The Assessment Program found that most CCR 

surface impoundments did not contain soils in detrimental volumes or configurations in the 

embankment that would indicate susceptibility to liquefaction. However, the assessment effort 

found that in embankments with a presence of soils susceptible to liquefaction, most CCR 

surface impoundments did not meet the required liquefaction FOS.

The Assessment Program found that many CCR surface impoundments had not 

undergone liquefaction potential analyses or post-liquefaction residual strength analyses in those 

instances in which liquefaction potential was identified (i.e., soils subject to liquefaction were 

present). The assessments gave impoundments a condition rating of “poor” if there was no 

information available to characterize the soils of the embankment, and a condition rating of 

“poor” or “fair” if post-liquefaction residual strength analysis of soils previously identified as 

being susceptible to liquefaction had not been available, with the rating dependent on the 

determined severity of the liquefaction potential in the embankment. Impoundments with 

calculated liquefaction factors of safety which did not meet or exceed 1.00 were given a 

condition rating of “poor.” As the Assessment Program advanced, many utilities independently 

conducted new or updated liquefaction potential analyses or residual strength analyses of CCR 

surface impoundments in anticipation of their facilities being assessed. By the end of the 

program, virtually all facilities had conducted or were in the process of conducting liquefaction 
Document submitted to conclude E.O.12866 Review

50

potential analyses or residual strength analyses. While some utilities noted concern over the 

costs of conducting additional liquefaction potential or residual strength studies, none found that 

completing these studies presented any significant engineering challenges. 

Based on its experience in the Assessment Program and subsequent review of numerous 

technical resources, EPA determined that a post-liquefaction residual strength factor of safety in 

the embankment of 1.00 is not sufficient. Liquefaction potential analysis and post-liquefaction 

residual strength analysis involves a larger degree of uncertainties, e.g., liquefiable stratum 

configuration, in assumptions and analysis which must be accounted for with a factor of safety 

above 1.00. The final rule therefore requires CCR surface impoundments which are constructed 

of soils determined to be susceptible to liquefaction to meet or exceed a liquefaction factor of 

safety of 1.20. EPA has determined that 1.20 is an appropriate liquefaction factor of safety based 

on several technical guidances and memos, including Federal Guidelines for Dam Safety: 

Earthquake Analyses and Design of Dams, Document 65, FEMA May 2005, which states that 

“post-liquefaction factors of safety are generally required to be a minimum of 1.2 to 1.3.” 17, 18, 19, 

20, 21

c. Impoundment Height and Relationship to Regulatory Requirements

 

17 US Bureau of Reclamation (USBR), “Water Operation and Maintenance Bulletin No. 222,” Denver, 

Colorado, December 2007.

18 http://www.oregon.gov/odot/hwy/bridge/docs/bddm/pdfs/psha.pdf

19 Canadian Dam Association. Canadian Dam Safety Guidelines, 2007, 88 pp.

20 Sonmez, H., 2003. Modification of the liquefaction potential index and liquefaction susceptibility 

mapping for a liquefaction-prone area (Inegol, Turkey), Env. Geology, (44): 862-871.

21 Seed, R.B., Cetin, O.K., Moss, R.E.S., Kammerer, A.M., Wu, J., Pestana, J.M., Riemer, M.F., Sancio, 

R.B., Bray, J.D., Kayen, R.E., Faris, A., 2003. Recent advances in soil liquefaction engineering: a unified 

and consistent framework, 26th annual ASCE L.A. Geot. Spring Sem., Long Beach, California, April 30, 

71 pp.
Document submitted to conclude E.O.12866 Review

51

During the Assessment Program, the Agency reviewed the stability issues related to 

various heights of impoundments. The Assessment Program concluded that impoundments with 

heights less than five feet or those retaining less than 20 acre feet were unlikely to cause 

significant environmental or economic loss should they undergo a catastrophic failure. The 

Agency’s review of MSHA and FEMA guidance also noted that “small” units were unlikely to 

cause significant losses should they fail. Based on the Agency’s experience and FEMA and 

MSHA’s guidance, the Agency has concluded that there is a substantial benefit in having 

impoundments which exceed a specified size threshold, i.e., height of five feet or more and 

capacity of 20 acre-feet or more or a height of 20 feet or more determine their static, seismic, and 

liquefaction FOS on a regular basis. The analyses and experience gained in conducting the 

Assessment Program indicates that a catastrophic failure of a CCR surface impoundment is 

unlikely to occur so long as the factors of safety are maintained or exceeded throughout the 

unit’s operating life. This conclusion is also consistent with relevant guidance and regulations 

which do not require such evaluations for units below a certain size threshold. 

d. Hazard Potential Ratings

Each impoundment assessed in the Assessment Program was given a Hazard Potential 

Classification rating of either Less-than-Low, Low, Significant, and High. Previous 

classifications were reviewed and amended as necessary to reflect guidance developed for the 

Assessment Program. The hazard potential ratings refer to the potential for loss of life or 

damage if there is a dam failure. The ratings do not refer to the condition or structural stability of 

the dam. Four hazard potential classifications were used in assessing the impoundments in the 

Assessment Program:

High Hazard Potential - Dams assigned the high hazard potential classification are 

those where failure or mis-operation will probably cause loss of human life.
Document submitted to conclude E.O.12866 Review

52

Significant Hazard Potential - Dams assigned the significant hazard potential 

classification are those dams where failure or mis-operation results in no probable loss of human 

life, but can cause economic loss, environment damage, disruption of lifeline facilities, or impact 

other concerns. Significant hazard potential classification dams are often located in 

predominantly rural or agricultural areas, but could be located in areas with population and 

significant infrastructure.

Low Hazard Potential - Dams assigned the low hazard potential classification are those 

where failure or mis-operation results in no probable loss of human life and low economic and/or 

environmental losses. Losses are principally limited to the owner’s property.

Less Than Low Hazard Potential - Dams which do not pose high, significant, or low 

hazard potential.

There is a substantial benefit in having owners or operators of all CCR impoundments 

determine the hazard potential classification of their units. The Assessment Program found that 

many CCR surface impoundments had not been given a hazard potential classification and 

consequently, their potential threat to human health and the environment if a failure were to

occur was not clearly identified, nor had response plans been developed to respond to any 

catastrophic failure. Moreover, these classifications should be updated over time, particularly to 

account for changes such as population growth, construction of key infrastructure, or changes to 

the impoundment’s size or operation. The Assessment Program also found that some states do

not classify CCR impoundments as “dams” and therefore those units may not be required to 

determine their hazard potential classification or otherwise evaluate the potential effects of a 

catastrophic failure. Consistent with the guidance from ASDSO, FEMA, and New Jersey, this 

rule requires that all diked CCR impoundments determine their hazard potential classification
Document submitted to conclude E.O.12866 Review

53

according to the definitions set out in today’s regulation. For those units with a hazard potential 

classification of Significant or High, the owner or operator of such impoundments is also 

required to develop an Emergency Action Plan to address the higher potential impacts of a 

potential failure. 

e. Condition Ratings

While the rule does require facilities to evaluate the same engineering factors that went 

into developing these ratings, the rule does not require that each impoundment be given a 

condition rating. After evaluation of the use of these ratings, the Agency determined that the

rating may have relied too heavily on subjective factors. For that reason, this rule requires that 

the qualified professional engineer certify, based on quantitative determinations, that an 

impoundment meets the requirements for FOS and hydraulic and hydrologic capacity. This 

approach is less subjective and allows the professional engineer to make quantifiable 

certifications.

 

IV. Bevill Regulatory Determination Relating to CCR from Electric Utilities and 

Independent Power Producers

As discussed in the preceding sections, in the proposed rule EPA reopened its August 

1993 and May 2000 Regulatory Determinations regarding CCR generated at electric utilities and 

independent power producers, to reevaluate whether regulation of CCR under RCRA subtitle C 

is necessary in light of subsequent information. EPA explained that this was based on several 

relatively recent developments, such as a newly completed quantitative risk assessment that 

concluded that the disposal of CCR in unlined waste management units posed substantial risks, 

with upper end risk estimates ranging from 10-2– 10-4. Citing to the recent structural failures of 

surface impoundments, the proposed rule also noted that these wastes have caused greater 
Document submitted to conclude E.O.12866 Review

54

damage to human health and the environment than EPA originally estimated. Finally, EPA 

explained that recently collected information regarding the existing state regulatory programs 

had called into question whether those programs, in the absence of national minimum standards 

specific to these wastes, had sufficiently improved to address the gaps originally identified in the 

May 2000 Regulatory Determination. EPA ultimately concluded that federal regulation of this 

material was necessary, but did not reach any conclusion as to whether regulation under subtitle 

D would be sufficient or whether regulatory under subtitle C would be necessary to adequately 

address the risks. 

Of the over 450,000 comments received on the proposed rule, the vast majority focused 

on whether the Bevill exemption should be retained, and the corresponding question of whether 

CCR regulations should be established under RCRA subtitle C or subtitle D. In terms of the 

sheer numbers, the majority of commenters supported a decision to revoke the Bevill exemption 

and to regulate CCR under a subtitle C rule. These commenters, largely individual members of 

the public and environmental groups, generally argued that the Bevill exemption should be 

revoked because state programs have failed to adequately regulate the disposal of CCR and 

because the risks associated with the management of these wastes are significant. In support of 

both points, these commenters pointed to the fact that the number of damage cases that have 

been discovered has increased substantially since the original 2000 Regulatory Determination, 

and have continued to grow since publication of the proposed rule in 2009.

By contrast, state organizations, individual states, and industry groups (electric utilities, 

recycling firms, trade associations), largely favored a subtitle D rule. Overall, these commenters 

raised concern about the costs of the subtitle C regime, arguing that the subtitle C requirements 

were more stringent than necessary to address the risks from CCR disposal. Commenters also 
Document submitted to conclude E.O.12866 Review

55

raised concern that regulation of these wastes under subtitle C would negatively affect the 

beneficial use of these materials, arguing that the stigma associated with regulating the disposal 

of CCR as a hazardous waste would “cripple” the current beneficial reuse market. Many of these 

commenters also argued that EPA lacks the legal authority to regulate these wastes under subtitle 

C on a variety of grounds, including claims that EPA entirely lacks the authority to revisit its 

Bevill Regulatory Determination, and that EPA had failed to comply with statutory procedures in 

doing so.

A. Deferral of a Final Decision on the Bevill Regulatory Determination for CCR Destined 

for Disposal

In determining whether the Bevill exemption should be retained for CCR, EPA must 

evaluate and weigh eight factors that were enumerated in section 8002(n) of RCRA. 42 U.S.C. § 

6921(b)(3)(C). The eight factors are: (1) the source and volumes of CCR generated per year; (2) 

present disposal and utilization practices; (3) potential danger, if any, to human health or the 

environment from the disposal and reuse of CCR; (4) documented cases in which danger to 

human health or the environment from surface runoff or leachate has been proved; (5) 

alternatives to current disposal methods; (6) the cost of such alternative disposal methods; (7) the 

impact of those alternatives on the use of coal and other natural resources; and (8) the current 

and potential utilization of CCR. 42 U.S.C. § 6982(n). 

EPA addressed each of these study factors in the 1988 and 1999 Reports to Congress, and 

in reaching our decisions in the August 1993 and the May 2000 Regulatory Determinations to 

maintain the Bevill exemption for CCR. 58 FR 42466 (August 9, 1993); 65 FR 32214 (May 22, 

2000). Consequently, in considering whether to reverse these Regulatory Determinations for 

CCR destined for disposal, EPA reexamined the RCRA section 8002(n) study factors against all 
Document submitted to conclude E.O.12866 Review

56

of the available data, which included both the data that formed the basis for the May 2000 

Regulatory Determination and the most recent data available. (See 75 FR 35150-35156.)

As discussed at length in the proposed rule, three of these factors weighed the most 

heavily in the Agency’s decision to reconsider its previous Regulatory Determinations. (See 75 

FR 35133 and 35156-35158.) The first of these related to the extent of the risks posed by the 

current management of these wastes. Since the 2000 Regulatory Determination, EPA had 

completed a quantitative risk assessment that estimated significant risks to human health and the 

environment. EPA’s 2010 CCR risk assessment estimated the cancer risk from arsenic that 

leaches into groundwater from CCR managed in units without composite liners to exceed EPA’s 

typical risk thresholds of 10-4to 10-6. For example, depending on various assumptions about 

disposal practices (e.g., whether CCR is co-disposed with coal refuse), groundwater interception 

and arsenic speciation, the 90th percentile risks from unlined surface impoundments ranged from 

2×10-2to 1×10-4. The risks from clay lined surface impoundments ranged from 7×10-3to 4×10-5. 

Similarly, estimated risks from unlined landfills ranged from 5×10-4to 3×10-6, and from 2×10-4

to 5×10-9for clay-lined landfills. EPA’s risk assessment also estimated Hazard Quotients 

(HQs)

22 above 1 for other metals, including selenium and lead in unlined and clay-lined units. 

However, a number of technical questions were raised regarding this quantitative risk assessment 

that called into question the accuracy of these risk estimates. 

A second and equally significant consideration related to how effectively state regulatory 

programs address the risks associated with the improper management of these wastes. The 

existing reports on state regulatory programs had called into question whether the trend in 

improving state regulatory regimes that EPA identified in May 2000 had materialized to the 

 

22 For more information on HQs please see Unit X. Risk Assessment of this preamble.
Document submitted to conclude E.O.12866 Review

57

degree anticipated in the Regulatory Determination. EPA noted concern about the lack of 

substantial details regarding the full extent of state regulatory authority over the disposal of these 

materials, and the manner in which states have, in practice, implemented this oversight. 

The final consideration, which is tightly related to the first two, was the recent 

information documenting continued instances involving the contamination of ground or surface 

water from the management of these wastes. Since the 2000 Regulatory Determination EPA had 

gathered or received information on 67 “proven or potential” cases involving damage to (i.e., 

contamination of) ground and surface water, and to human health and the environment from 

improper management of CCR in landfills and surface impoundments. These also included cases 

involving the structural failure of surface impoundments and the catastrophic release of CCR.

For each of these key areas, EPA identified a number of issues on which the absence of 

critical information prevented the Agency from reaching an initial decision on whether to revise 

the Bevill Determination. Some of these issues or uncertainties have been resolved during the

development of the final rule, either as a result of information received from commenters or 

through additional information and analyses EPA obtained or developed, which were held out for 

comment in subsequent NODAs. See 75 FR 35128 (October 21, 2010) and 78 FR 46940 (August 

2, 2013). However, as discussed in more detail below, critical information necessary to a final 

Regulatory Determination is still lacking in two of these three areas. This information bears 

directly on the extent and magnitude of the risks over the course of the next several years, and 

the degree to which those risks can be managed sufficiently under each of the two regulatory 

structures available to the Agency. In the absence of this information, EPA is unable to reach a 

conclusion on the issue that is central to a Bevill Determination: whether the risks presented by 

management of CCR waste streams can only be adequately mitigated through regulation under 
Document submitted to conclude E.O.12866 Review

58

RCRA subtitle C. As a consequence, EPA is deferring a final Regulatory Determination for these 

wastes.23

Nevertheless, the record is clear that current management of these wastes can present, 

and in many cases has presented, significant risks to human health and the environment. 

Although EPA cannot reach conclusions as the full extent or magnitude of those risks over the 

long term, the current level of risk clearly warrants the issuance of federal standards to ensure 

consistent management practices and a national minimum level of safety. 

In the following sections, EPA describes the information that was obtained over the 

course of the rulemaking relating to each area of concern, and the extent to which the new 

information addressed the issue. 

1. Risks Posed by Current Management of CCR and Potential Danger to Human Health 

from the Disposal of CCR

In the proposed rule, EPA specifically noted that several uncertainties remained in the 

Agency’s quantitative risk analysis of the current management of CCR. Chief among these 

uncertainties was the evolving character and composition of CCR due to electric utility upgrades 

and retrofits of multi-pollutant controls needed to comply with the emerging Clean Air Act 

(CAA) requirements, which could present new or otherwise unforeseen contaminant issues (e.g., 

addition of calcium bromide to coal prior to combustion increasing mercury capture; use of 

 

23 Because EPA is deferring its final Bevill Determination, EPA has not responded to comments that 

pertain exclusively to that issue. However EPA has responded to significant comments that relate to 

topics that are otherwise relevant to the final subtitle D regulation. For example, because EPA is relying 

on the damage cases to support certain aspects of the technical requirements, EPA has responded to 

comments relating to the accuracy of the facts involved in the damage cases. EPA has not, however, 

responded to many comments on state programs because the Agency has made no final conclusions on 

the adequacy of those programs and is not relying on state programs to support any of the final rule’s 

provisions. 
Document submitted to conclude E.O.12866 Review

59

selective catalytic reduction for post-NOX controls forming hexavalent chromium). As EPA 

explained, changes to fly ash and other types of CCR is expected to occur as a result of increased 

use and application of advanced air pollution control technologies in coal-fired power plants. 

These technologies include flue gas desulfurization (FGD) systems for SO2 control, selective 

catalytic reduction (SCR) systems for NOX control, and activated carbon injection (ACI) systems 

for mercury control. These technologies are being installed or are expected to be installed in 

response to federal regulations, state regulations, legal consent decrees, and voluntary actions 

taken by industry to adopt more stringent air pollution controls. Use of these more advanced air 

pollution control technologies reduces air emissions of metals and other pollutants in the flue gas 

of a coal-fired power plant by capturing and transferring the pollutants to the fly ash and other air 

pollution control residues. Previous EPA studies of whether increased pollutant content would 

increase the risks correspondingly were inconclusive. For example, EPA evaluated the 

environmental fate of metals that are captured in CCR through use of enhanced air pollution 

controls, by characterizing the leaching behavior of 73 air pollution control residues, using the 

Leaching Environmental Assessment Framework (LEAF) methodology. Materials were tested 

over the pH conditions and liquid – solid ratios expected during management via land disposal or 

beneficial use. Leachate concentrations for most metals were highly variable over a range of coal

type, facility configurations, and air pollution control residues. In addition, the data showed

significantly different leaching behavior for similar residue types and facility configurations. 

Overall, the variability in leaching of the metals in the CCR was greater than the variability in 

totals concentrations by several orders of magnitude, suggesting that total pollutant content may 
Document submitted to conclude E.O.12866 Review

60

not be predictive of leaching behavior, and consequently the risks.24

The Agency received no data from commenters that would aid in resolving this 

uncertainty. To try to establish some parameters around the uncertainty, EPA attempted to 

develop estimates of the extent to which this issue could meaningfully affect the risks. 

As an initial step, EPA focused on mercury pollution controls, as mercury levels in these 

wastes was an issue of particular concern in the public comments. It has been established that 

mercury pollution controls can affect both the mercury content and the general leaching behavior 

of ash (US EPA 2006, 2008, 2009). Using the limited data available, EPA attempted to evaluate 

the extent to which mercury controlled wastes could ultimately affect the overall risk associated 

with disposal of CCR. 

EPA conducted a sensitivity analysis that filtered the full 2014 risk assessment results for 

the subset of fly ash samples generated by facilities that have currently installed ACI systems. 

The samples were collected from five different facilities that were either installing or evaluating 

an ACI system for increasing mercury capture. At each facility, samples were collected both 

before and after the installation of an ACI system. Ultimately the results were inconclusive, 

likely because of the small sample size, and EPA can draw no conclusions about the exact effects 

of ACI systems on the risks from CCR disposal. Nevertheless, the analysis provided some useful 

information. Capturing and transferring pollutants from air emission to the fly ash and other air 

pollution control residues would normally be expected to increase the risks associated with 

disposal of these wastes. EPA’s analyses, however, showed only a marginal difference in risks 

for ash generated with or without the use of an ACI system, and in some instances the risks 

 

24 Thorneloe, S, Kosson,D., Sanchez, F., Garrabrants, A.C., and Helms, G., Evaluating the Fate of Metals 

in Air Pollution Control Residues from Coal-Fired Power Plants, Environ. Sci. Technol. 2010, 44, 7351–

7356.
Document submitted to conclude E.O.12866 Review

61

decreased slightly with the addition of activated carbon. The significance of these results should 

not be overstated--the observed decreases were not consistent and were thought to be an artifact 

of the relatively small number of model iterations. It is also important to remember that these 

results provide no information about the potential effects from the installation of FGD systems 

for SO2 control, or SCR systems for NOX control, any of which could also significantly affect the 

characteristics of the wastes. But these results also suggest that EPA should be cautious about 

assuming that the risks will necessarily increase as a result of the imposition of additional air 

pollution controls. 

Other uncertainties in the risk assessment developed for the proposal related to the extent 

to which some sampled data with high concentrations used in the risk assessment accurately 

reflect coal ash leaching from landfills or surface impoundments. For example, as explained in 

the proposed rule, some data reflected pore water taken in the upper section of a surface 

impoundment where coal refuse was placed. There were acid generating conditions and high 

concentrations of arsenic, but the data demonstrated that the underlying coal ash neutralized the 

acid conditions and greatly reduced the arsenic which leached from the bottom of the 

impoundment. EPA also noted that much of the pore water samples and leachate data were 

several years old, and questions had been raised whether these data accurately reflected current 

management practices. Finally, EPA noted that recent research indicated that traditional leach 

procedures (e.g., TCLP and SPLP) may underestimate the actual leach rates of toxic constituents 

from CCR under different field conditions.

First, regarding the question of appropriate pH conditions in CCR disposal units, and the 

resulting leachate concentrations in impoundments where coal refuse was placed, EPA obtained 

data during the development of this rule directly relevant to this issue. A survey conducted by the 
Document submitted to conclude E.O.12866 Review

62

Electric Power Research Institute (EPRI) in 1995 had shown that 34 percent of unlined landfills 

and 68 percent of unlined surface impoundments actively managed CCR with coal refuse. 

However, more recent data collected by EPA as part of the Clean Water Act ELG rulemaking in 

2009-2010 indicates that this management practice has declined significantly to approximately 

five percent of current units. 

EPA also obtained sufficient data to resolve concerns about the accuracy of the 

concentrations in pore water and leachate used in the risk assessment. EPA received a substantial 

amount of data on CCR chemical constituents from commenters, which included total 

concentrations, pore water, and leaching test results for various types of CCR, i.e., bottom ash, 

FGD gypsum, FGD sludge, fly ash cenospheres, boiler slag, and combined waste streams. This 

included data from several EPRI reports, which provided field leachate results for bottom ash, fly 

ash, and FGD solids from a number of landfills and surface impoundments. EPA also received 

leachate data from the Alaska Department of Environmental Conservation, the Michigan 

Department of Natural Resources and Environment (MI DNRE), and from the Maryland 

Department of the Environment on total metals, TCLP, and SPLP results for bottom ash and fly 

ash. Included among these data were TCLP results for 102 CCR samples and 12 FGD gypsum 

samples, and two landfill leachate samples, as well as several laboratory reports on CCR leachate

from 2008 through 2010. EPA also received several reports from the University of North Dakota 

Energy & Environmental Research Center, with leaching test results for 58 fly ash, five FGD, 

and four FGD gypsum samples using various leaching methods other than TCLP, and TCLP 

mercury results for 15 fly ash samples, as well as leaching test results for five fly ash and two 

bottom ash samples using 18-hr, 30-day, and 60-day leach methods, plus bulk and trace element 

data for five fly ash samples, two bottom ash samples, and one slag sample. (See 75 FR 35128.) 
Document submitted to conclude E.O.12866 Review

63

In addition to the data submitted by commenters, EPA's Office of Research and 

Development (ORD), in collaboration with Vanderbilt University (VU), developed additional 

CCR leaching data using a revised methodology, the Leaching Environmental Assessment 

Framework, or LEAF, consisting of four methods that evaluate leaching potential for various 

waste forms at different plausible pH values and liquid-solid ratios, in order to more accurately 

simulate leaching potential over a variety of field conditions. The LEAF methods went through 

validation working with 20 different laboratories, different waste matrices, and documented in 

two EPA reports finding good agreement between the labs for the four methods.25 In addition, 

EPA compiled decades of data for ten different case studies to compare field and laboratory 

leach data.26 These data also showed LEAF methods to be a good predictor of field leachate 

behavior using geochemical speciation modeling for factors such as oxidation that are difficult to 

account for in the lab. When considered along with the methods validation, the field-to-lab 

leachate data comparison provides additional confidence that LEAF methods can more 

accurately predict environmental release over a range of materials, waste form, pH, liquid-solid 

 

25 Garrabrants A.C., D.S. Kosson, H.A. van der Sloot, F. Sanchez and O. Hjelmar (2010) Background 

information for the Leaching Environmental Assessment Framework (LEAF) Test Methods, EPA-600/R10/170, U.S. Environmental Protection Agency, Air Pollution Prevention and Control Division, 

December 2010.

Garrabrants A.C., D.S. Kosson, L. Stefanski, R. DeLapp, P.F.A.B. Seignette, H.A. van der Sloot, P. 

Kariher and M. Baldwin (2012a) Interlaboratory Validation of the Leaching Environmental Assessment 

Framework (LEAF) Method 1313 and Method 1316, EPA/600/R-12/623, U.S. Environmental Protection 

Agency, Air Pollution Prevention and Control Division, September 2012.

Garrabrants A.C., D.S. Kosson, R. DeLapp, P. Kariher, P.F.A.B. Seignette, H.A. van der Sloot, L. 

Stefanski and M. Baldwin (2012b) Interlaboratory Validation of the Leaching Environmental Assessment 

Framework (LEAF) Method 1314 and Method 1315, EPA-600/R-12/624, U.S. Environmental Protection 

Agency, Air Pollution Prevention and Control Division, September 2012.

26 Kosson D.S., van der Sloot, H.A., Seignette, P.F.A.B. 2014. Leaching Test Relationships, Laboratoryto-Field Comparisons and Recommendations for Leaching Evaluation using the Leaching Environmental 

Assessment Framework (LEAF), EPA-600/R-14/061. EPA Office of Research and Development, 

National Risk Management Research Laboratory, Research Triangle Park, NC, 27711. December.
Document submitted to conclude E.O.12866 Review

64

ratio, and other parameters influencing leaching behavior such as calcium depletion for a 

material. 

In updating the risk assessment for the final rule, EPA relied on surface impoundment 

pore water data and impoundment wastewater data, including the data submitted by commenters. 

For landfills, EPA only used LEAF data to characterize the leachate for the range of materials 

resulting from various air pollution control technologies. The CCR data documented in three 

EPA reports27 and summarized in Thorneloe et al, 201028 provides a robust characterization of 

air pollution control residues from coal-fired power plants and indicates that leaching rates can 

vary by several orders of magnitude, depending on pH levels and the amount of liquid that 

comes into contact with the CCR solids (i.e., the liquid to solid ratio). 

The 2014 risk assessment incorporates these new data, and accounts for both the pH of 

the waste in field conditions, as well as the liquid-to-solid ratio of the leachate and CCR, which 

effectively addresses the concerns raised in the proposed rule that TCLP and SPLP methods 

could underestimate leachate concentrations. 

 

27 Sanchez F., R. Keeney, D.S. Kosson and R. DeLapp (2006) Characterization of Mercury-Enriched Coal 

Combustion Residues from Electric Utilities using Enhanced Sorbents for Mercury Control, EPA-600/R06/008, U.S. Environmental Protection Agency, Air Pollution Prevention and Control Division, February 

2006. 

Sanchez F., D.S. Kosson, R. Keeney, R. DeLapp, L. Turner and P. Kariher (2008) Characterization of 

Coal Combustion Residues from Electric Utilities using Wet Scrubbers for Multi-pollutant Control, EPA600/R-08/077, U.S. Environmental Protection Agency, Air Pollution Prevention and Control Division, 

July 2008. 

Kosson D.S., F. Sanchez, P. Kariher, L.H. Turner, R. DeLapp, and P. Seignette (2009) Characterization of 

Coal Combustion Residues from Electric Utilities – Leaching and Characterization Data, EPA-600/R09/151, U.S. Environmental Protection Agency, Air Pollution Prevention and Control Division, 

December 2009.

28 Thorneloe S.A., D.S. Kosson, F. Sanchez, A.C. Garrabrants and G. Helms (2010) “Evaluating the fate 

of metals in air pollution control residues from coal-fired power plants,” Environmental Science and 

Technology, 44, 7351-7356.
Document submitted to conclude E.O.12866 Review

65

A further area of uncertainty related to one of the primary inputs into the risk assessment. 

As noted in the proposed rule, the Agency’s risk estimates were based on the existing cancer 

slope factor of 1.5 mg/kg/d-1for arsenic in EPA’s Integrated Risk Information System (IRIS). 

However, EPA noted that was in the process of revaluating the arsenic cancer slope factor in 

light of recent recommendations from the National Research Council (NRC) of the National 

Academy of Sciences (NAS) in ‘‘Critical Aspects Arsenic in Drinking Water, 2001 Update.’’ In 

the proposal, EPA estimated that using this NRC data analysis would increase the individual risk 

estimates by approximately 17 times.

EPA is currently evaluating the arsenic cancer slope factor in light of more recent NRC 

recommendations, regarding the approach and the science for estimating cancer and non-cancer 

risk in ‘‘Critical Aspects of EPA’s IRIS Assessment of Inorganic Arsenic, (NRC 2013).’’ EPA is 

in the process of implementing these recommendations, but to date has been unable to finalize its 

IRIS reassessment. Nor did EPA receive any other information during the development of this 

final rule that would help to resolve this uncertainty. 

A final source of uncertainty in the risk assessment developed for the proposed rule 

related to the potential impact from the interception of contaminated groundwater plumes by 

surface water bodies that exist between a waste management unit and a down-gradient drinking 

water well. It is common for coal-fired utilities to be located near water bodies, which are used 

as a source of cooling water and waste conveyancing. Releases from surface impoundments 

located in close proximity to water bodies can be intercepted, which can significantly affect the 

contaminants that reach drinking water wells. For example, surface impoundments are 

commonly placed next to rivers, which can intercept the leachate plume and prevent 

contamination of drinking water wells on the other side of the river. Also, in such circumstances 
Document submitted to conclude E.O.12866 Review

66

the direction of groundwater flow on both sides of the river may be towards the river; thus, the 

drinking water well on the opposite side of a river may not be impacted.

Over the course of the rulemaking, EPA was able to obtain sufficient data to model the 

impact from interception of contamination by surface water bodies. The risk assessment 

developed for the final rule accounts for the interception of the groundwater contamination 

plume by surface water bodies, and the resulting decrease in constituent mass to downstream 

drinking water sources. As a consequence of this modeling, the median risks for surface 

impoundments and landfills were substantially lower than both the high-end and median risks 

modeled in the 2010 risk assessment, i.e., by approximately an order of magnitude. 

2. Adequacy of Existing State Regulatory Oversight

The assessment of state regulatory programs in the proposed rule was based largely on 

two reports: a joint U.S. Department of Energy (DOE) and EPA study completed in 2006, “Coal 

Combustion Waste Management at Landfills and Surface Impoundments, 1994–2004,” and a 

2009 survey conducted by the Association of State and Territorial Solid Waste Management 

Officials (ASTSWMO). EPA’s preliminary conclusion was that while states seem to be 

regulating landfills to a greater extent than in 2000, significant gaps in state programs appeared 

to remain, particularly with respect to the oversight of surface impoundments. 

In reaching this conclusion EPA noted the following findings from the DOE/EPA study: 

only 19 percent (three out of 19) of the surveyed surface impoundment permits included 

requirements addressing groundwater protection standards (i.e., contaminant concentrations that 

cannot be exceeded) or closure/post-closure care, and only 12 percent (two out of 12) of 

surveyed units were required to obtain bonding or financial assurance. The EPA/DOE report also 

concluded that approximately 30 percent of the net disposable CCR generated was potentially 
Document submitted to conclude E.O.12866 Review

67

exempt from all state solid waste permitting requirements (EPA/DOE Report at pp 45–46). For 

example, at the time of the report, Alabama did not regulate CCR disposal under any state waste 

authority and nor had a dam safety program. Texas (the largest coal ash producer) did not require 

permits for waste managed on-site, which is defined as waste managed at any site owned by the 

generator, up to 50 miles away from the generating facility. Finally, the report found that a 

number of states only regulated surface impoundments under CWA authorities, and consequently 

primarily addressed the risks from effluent discharges to navigable waters, but did not require 

liners or groundwater monitoring.

The more recent 2009 ASTSWMO survey reached similar conclusions. With respect to 

liner requirements, 36 percent of surveyed states did not have minimum liner requirements for 

CCR landfills, while 67 percent did not have CCR liner requirements for surface impoundments. 

Similarly, 19 percent of states surveyed did not have minimum groundwater monitoring 

requirements for landfills and 61percent did not have groundwater monitoring requirements for 

surface impoundments. The 2009 ASTSWMO survey also indicated that only 36 percent of 

states regulated the structural stability of surface impoundments.

In the proposal, EPA identified several issues that complicated its preliminary assessment 

and prevented the Agency from reaching overall conclusions as to the adequacy of state 

regulatory programs. First, EPA raised concern about the absence of any real details in the two 

reports regarding how states, in practice, oversee the disposal or other solid waste management 

of CCR. For example, even though the disposal units might not be regulated under the state solid 

waste provisions, some states may use performance based standards or implement requirements 

to control CCR landfills and surface impoundments under other state programs. Second, EPA 

noted that most of the more recent data primarily focused on the requirements applicable to new 
Document submitted to conclude E.O.12866 Review

68

management units, which only represented approximately 10 percent of currently operating 

units. EPA had little, if any, information that described the extent to which states and utilities 

implemented had imposed requirements, such as groundwater monitoring, on the many existing 

landfills and surface impoundments that receive CCR. Moreover, the information in the record 

for the proposal with respect to these older units was fifteen years old. EPA assumed it to be 

unlikely that states would have required existing units to install liners, but suggested states may 

have been more likely to have imposed groundwater monitoring for such units over the last 15 

years.

EPA also identified several issues that would be relevant to the Agency’s evaluation of 

the overall adequacy of state regulatory programs. Specifically, EPA explained that it would 

consider how state regulatory programs have, in practice, evaluated and imposed requirements to 

address: (1) leachate collection; (2) groundwater monitoring; (3) whether a unit must be lined, 

and the type of liner needed; (4) the effectiveness of existing management units as opposed to 

new management units; (5) whether the state requires routine analysis of CCR; (6) whether 

financial responsibility requirements are in place for the management of CCR; (7) the extent of 

permit requirements, including under what authorities these disposal units are permitted, the 

types of controls that are included in permits, and the extent of oversight provided by the states, 

(8) whether state programs include criteria for siting new units; (9) the extent of requirements for 

corrective action, post-closure monitoring and maintenance; (10) the state’s pattern of active 

enforcement and public involvement; and (11) whether or not these facilities have insurance 

against catastrophic failures.

EPA received a substantial amount of information on state programs from public 

commenters. Extensive comments were submitted by a coalition of environmental groups, 
Document submitted to conclude E.O.12866 Review

69

outlining the alleged gaps in state regulatory programs applicable to the management of CCR. 

These comments contained a comprehensive analysis of 37 state programs based on the findings 

of the DOE/EPA 2006 report as well as on an independent compilation of state program 

requirements. According to these commenters’ analysis, only four states (representing 

approximately 4 percent of the CCR generated in the U.S. in 2005) required groundwater 

monitoring in all new and existing landfills, and only six states (representing approximately 19

percent of the CCR generated in 2005) required groundwater monitoring in all new and existing 

surface impoundments; only five states (representing approximately 7 percent of the CCR 

generated in 2005) required composite liners for all new landfills; and only four states 

(representing approximately 19 percent of the CCR generated) required composite liners for all 

new surface impoundments. The commenters’ analysis discounted any state law that included 

any provision that granted permit writers discretion to modify the requirement on a case-by-case 

basis, and/or to grant waivers and exemptions based on the waste’s toxicity, onsite location, and 

management practice.

EPA also received comments from ASTSWMO, the Environmental Council of the States

(ECOS), and 36 individual states. In its comments, ASTSWMO submitted a report with revisions 

of the aggregated statistics in its 2009 report, which they claim demonstrated that state CCR 

programs were more robust than described in the proposed rule. These comments generally 

agreed with EPA’s conclusion that state requirements for key CCR requirements are typically 

more robust for landfills than for surface impoundments. ASTSWMO’s comments included the 

following examples: 71percent of the surveyed states required a liner for landfills, compared to 

65percent that required that surface impoundments be lined; 87 percent of surveyed states 

required monitoring at landfills, compared to 67 percent of states that required groundwater 
Document submitted to conclude E.O.12866 Review

70

monitoring at surface impoundments; and while 83 percent of surveyed states require structural 

stability monitoring at landfills, only 64 percent of surveyed states require it at surface 

impoundments. The sole exception related to permit requirements, where the report claimed that 

91 percent of the surveyed states require a permit of some type for surface impoundments, as 

compared to 86 percent of states that require a permit for landfills. In addition, ASTSWMO 

claimed that all 42 surveyed states had the authority to require remediation. The report also 

alleged that in 43 of 44 states, states had the authority to require surface impoundments to 

implement repair and maintenance efforts during operation. ASTSWMO also claimed that 43 out 

of 44 states require that steps be taken to protect human health and the environment, and that 41 

of 43 states also had authority to require closure.

According to this revised survey, state requirements also vary with respect to whether 

they applied to all waste units, or only to new units or lateral expansions. ASTSWMO stated

that in 34 percent of the surveyed states, liners requirements applied equally to new and existing 

landfill units, and to both existing and new surface impoundments in 46 percent of the surveyed 

states. Similarly, ASTSWMO stated that groundwater monitoring was required for both existing 

and new landfills in 82 percent of the surveyed states, and to both existing and new surface 

impoundments in 74 percent of the surveyed states.

Nineteen states and state organizations also directly responded to the environmental 

groups’ report by submitting comments on their programs, although only four of these states 

were among the leading CCR generators: Kentucky, North Dakota, Ohio, and Michigan. These 

states identified specific instances where the assertions made by the environmental groups were 

factually incorrect or omitted relevant information. In response to both the proposed rule and the 

NODA (76 FR 63252, October 12, 2011) most states provided only summaries of their 
Document submitted to conclude E.O.12866 Review

71

regulatory programs rather than detailed descriptions. 

As EPA explained in the proposed rule, there are significant limitations to the kind of 

aggregated survey statistics presented in ASTSWMO’s comments. Such statistics fail to provide 

the information necessary to meaningfully address the question of how, in practice, state 

programs regulate the relevant risks presented by the management or disposal of these wastes, 

which was the issue that EPA explained was necessary to resolve. For example, even assuming 

that 91 percent of the surveyed states actually do require a permit of some type for surface 

impoundments, this provides no information on the nature or extent of the specific requirements 

in the permit. As noted in the proposal, most CCR surface impoundments are regulated under a 

NPDES permit, and while the risks from effluent discharges to navigable waters are addressed, 

these units are not subject to the provisions designed to protect groundwater, such as liners or 

groundwater monitoring. Nor does it address the extent of the requirement; for example, 

although Texas generally requires landfills to be permitted and to monitor groundwater, the 

majority of CCR units are exempt from these requirements because all industrial wastes 

managed on-site (i.e., any site owned by the generator, up to 50-miles away from the generator’s 

facility) are exempt. Finally, since the ASTSWMO survey does not identify the individual 

surveyed states but merely presents aggregated statistics, this information cannot be correlated 

with the amount of CCR generated, which significantly limits its value; for example, information 

demonstrating the strength of the regulatory program in a state responsible for 2 percent of the 

net CCR generated nationally is less significant than similar information on a state responsible 

for 25percent of the net CCR generated. 

In addition to the information provided by commenters, EPA independently reviewed 

state statutes and regulations, with a more detailed focus on the sixteen states responsible for 
Document submitted to conclude E.O.12866 Review

72

approximately 74 percent of the CCR generated in 2009. It is clear from this review, as well as 

from information submitted by the commenters, that the degree of state regulatory oversight of 

these wastes and the overall protectiveness of the particular state programs varies widely. 

Overall, the information from commenters and from EPA’s own review of state programs 

generally confirms EPA’s original conclusion that significant gaps remain in many state 

programs. Some programs provide minimal or no regulatory oversight of CCR disposal units. 

For example, Arizona, New Mexico, and Utah have no regulations applicable to CCR disposal 

units or entirely exempt CCR from state regulations governing solid waste. Similarly, 

Mississippi, Montana, and Texas (the largest coal-ash producer) exempt the on-site disposal of 

CCR (as “non-hazardous industrial solid waste”) from some or all key requirements, such as 

permits or groundwater monitoring.29 Such exemptions would cover most of the disposal of CCR 

within the state, as the majority of utilities dispose of their CCR on-site. Other states, such as 

Florida, Indiana, Ohio and Pennsylvania, exempt CCR landfills or “monofills” from many 

requirements. For example, Indiana regulations consider surface impoundments that are dredged 

at least annually to be “storage units” that are exempt from solid waste regulations, including 

from corrective action requirements. Many of these states are among the leading generators of 

CCR wastes. In total, EPA estimates that approximately 20 percent of the net disposable CCR is 

entirely exempt from state regulatory oversight. 

State programs that entirely exempt CCR management from regulatory oversight, 

however, are the exception. Most states do regulate the management of CCR to varying degrees, 

although the particular requirements can vary significantly. Still, some general conclusions can 

be drawn.

 

29 See 30 TX ADC 335.2(d); 
Document submitted to conclude E.O.12866 Review

73

Most CCR surface impoundments are permitted exclusively under NPDES or other 

surface water pollution prevention programs. In these states, requirements to protect 

groundwater, such as liners or groundwater monitoring systems, are frequently less robust than 

the corresponding requirements applicable to CCR landfills. 

Many state programs require that new disposal units be lined and groundwater 

monitoring systems installed, although many also exempt existing waste units from the liner and 

groundwater monitoring requirements. Consequently, for newer units, the facts are less alarming: 

89 percent of the 114 CCR surface impoundments constructed between 1994 and 2010 have 

liners, and 70 percent have composite liners. Similarly, 37 of 45 CCR surface impoundments 

EPA surveyed had installed groundwater monitoring systems. By contrast, 79 percent of the 

landfills constructed during this timeframe had installed liners, and only 58 percent are 

composite-lined. However the majority of the older (pre-1994) waste units still lack liners; 63

percent of older landfills have no liners and 63 percent and 24 percent of older surface 

impoundments have either no liners or clay liners, respectively). Information on the extent of 

groundwater monitoring at older units was either unavailable, or was too unreliable to support 

any conclusions as to the overall number or percentage of older units with groundwater 

monitoring systems in most states. ASTSWMO’s comments in response to the October 2011 

NODA identified eight states30 that required groundwater monitoring at existing facilities, but 

only a few of these states addressed this issue in their comments. EPA has some anecdotal 

evidence on the status of groundwater monitoring in six states, including four states that are 

among the leading CCR generators. In the wake of the Kingston TVA spill, groundwater 

monitoring wells were installed at 12 of Illinois’s existing surface impoundments, almost 

 

30 Georgia, Illinois, Indiana, Iowa, Montana, Ohio, Pennsylvania, and South Carolina. 
Document submitted to conclude E.O.12866 Review

74

doubling the number of monitored surface impoundments in the state. However, 55 additional 

surface impoundments, both active and inactive, still lack groundwater monitoring systems. In 

Ohio, 44 CCR units, out of a total of 57 CCR units in the state (42 surface impoundments and 15 

landfills) still lack groundwater monitoring, even though all of the surface impoundments were 

permitted decades ago under Ohio’s NPDES program. Ohio acknowledged in their comments 

that the extent of groundwater risks in the state is poorly documented, as 40 out of 44 unlined 

CCR units do not have a groundwater monitoring system. In sum, the available information is 

limited, but at least some of that information indicates that significant gaps remain with respect 

to the implementation of groundwater monitoring requirements under some state regulatory 

programs.

Of the states that require groundwater monitoring, most appear to require monitoring 

wells to be placed around the waste unit boundary, although the distance from the unit boundary 

varies from 50 feet to 150 meters. However, some state programs also authorize a buffer zone or 

a “zone of discharge,” which allows the facility to defer remediation of groundwater 

contamination for some period of time, usually until the contaminant plume has migrated to the 

facility site boundary. Florida, Illinois, North Dakota, and Tennessee are among that states with 

such a regulatory provision. For example, under Florida regulations, primary and secondary 

MCLs do not apply even beyond the “zone of discharge,” absent a specific order by state 

regulatory authorities. 

Most state programs allow the state regulatory authority to grant variances or exemptions 

for some or all of the requirements based on site-specific factors. For example, all of the 

following states require groundwater monitoring at CCR surface impoundments, but also 

authorize the regulatory authority to exempt or waive those requirements: Alabama, Florida, 
Document submitted to conclude E.O.12866 Review

75

Georgia, Illinois, Indiana, Kentucky, North Caroline North Dakota, Pennsylvania, and West 

Virginia. Contrary to the analysis presented by the environmental groups’ comments, the mere 

fact that state law grants a permit authority the discretion to tailor requirements to account for a 

facility’s site specific conditions does not support a conclusion that the regulatory program is 

necessarily inadequate. In fact, EPA noted in the proposal that one of the strengths of the subtitle 

C program was that, as a result of the permit process, requirements could be tailored to account 

for site specific conditions. Nor does the existence of a waiver process provide any evidence of 

actual practices; in their comments, a few states acknowledged that state law allowed for 

variance, but asserted that none had been requested. 

To complicate matters further, several states explained that while state law does not 

mandate certain requirements, state regulatory authorities have, in practice, begun to require 

them in more recent permits. For example, several states, including Ohio, Texas, Michigan, 

Florida, and Kentucky, noted that recent practice was to require older disposal units to retrofit or 

close where they failed to meet relevant standards. Similarly, it appears that in the 16 leading

CCR-generating states, 94 percent of new landfills have installed liners (either composite or 

clay), although only 19 percent of these state programs actually mandate CCR landfills to install 

a liner. And although only 6 percent of these state programs require installation of a liner in a 

new surface impoundment, 75 percent of new CCR surface impoundments in these states are 

lined. 

All of this information suggests that, at least in some cases, the concerns raised in the 

proposal regarding the protectiveness of state programs remain warranted. But it also is clear it 

would be impossible to accurately evaluate whether, in practice, state programs are protective 

without reviewing individual permits decisions and permit requirements. Such an evaluation 
Document submitted to conclude E.O.12866 Review

76

would necessarily involve not only a review of the specific permit requirements, but also the site 

conditions and other factual bases supporting the decision to impose the particular requirements. 

Unfortunately, this information was not provided by commenters or found in any source 

currently available to the Agency. 

3. Documented Cases in Which Danger to Human Health or the Environment from Surface 

Run-off or Leachate Has Been Proved 

In the proposed rule, EPA described the information it had compiled on specific cases 

where CCR mismanagement had caused harm to human health or the environment since the 

2000 Regulatory Determination. Specifically, EPA explained that it had identified 27 proven 

damage cases: 17 cases of damage to groundwater, and ten cases of damage to surface water, 

seven of which are ecological damage cases. Sixteen of the 17 proven damage cases to 

groundwater involved disposal in unlined units; for the one additional unit, it is unknown 

whether the unit was lined. EPA also identified 40 potential damage cases to groundwater and 

surface water. The Agency noted that these numbers likely underestimated the number of 

damage cases and its expectation that additional cases of damage would be found if a more 

comprehensive evaluation was conducted, particularly since much of this waste has been (and 

continues to be) managed in unlined disposal units. EPA also noted its concern that several of the 

new damage cases involved activities that differ from prior damage cases, including the 

catastrophic release of waste due to the structural failure of CCR surface impoundments, such as 

the dam failures that occurred in Martins Creek, Pennsylvania and Kingston, Tennessee, as well 

as the large-scale placement, akin to disposal, of CCR, under the guise of “beneficial use.”

EPA noted as well that it had received new reports from industry and environmental and 

citizen groups regarding damage cases. Industry provided information to demonstrate that many 
Document submitted to conclude E.O.12866 Review

77

of EPA’s listed proven damage cases did not meet EPA’s criteria for a damage case to be 

considered “a proven damage case,” that had been developed for purposes of the Bevill 

Regulatory Determinations. Environmental and citizen groups, on the other hand, had submitted 

reports alleging the existence of more recent damage cases beyond those EPA had previously 

documented. 

EPA raised questions concerning the following areas associated with the damage cases; 

first, whether the damage cases discovered to date accurately reflected the true number of 

damage cases associated with the mismanagement of CCR. Second, EPA highlighted concern 

regarding the accuracy of the available information on damage cases, as in certain instances, 

much of the information was largely anecdotal. EPA therefore specifically solicited comments 

from state regulatory authorities and the facilities involved with the incidents, in the hope of 

obtaining direct evidence of the facts in each case and to obtain a better understanding of the 

nature of the damage caused by past and current management practices. For the same reason, on 

October 12, 2011, EPA published a NODA, soliciting comment on the extensive reports received 

during the original comment period on the proposed rule. (See 76 FR 63252.)

As discussed in more detail in Unit XI, EPA received a significant number of comments 

on this topic, both during the original comment period on the proposal, and in response to the 

October 12, 2011 NODA. EPA received information on additional damage cases from a number 

of citizen groups. This includes the report from Environmental Integrity Project and Earthjustice

titled, “Out of Control: Mounting Damages From Coal Ash Waste Sites,” which presents 

information on 31 alleged CCR damage cases that were not included or were not recognized as 

damage cases in EPA's July 2007 report. EPA also received an August 26, 2010 report by the 

Environmental Integrity Project, Earthjustice, and the Sierra Club titled “In Harm's Way: Lack of 
Document submitted to conclude E.O.12866 Review

78

Federal Coal Ash Regulations Endangers Americans and Their Environment,” which presented 

an additional 39 alleged CCR damage cases.31 EPA also received information on ten additional 

damage cases from state officials in Michigan and Wisconsin. 

EPRI submitted two draft reports titled “Evaluation of Coal Combustion Product Damage 

Cases: Volume 1: Data Summary and Conclusions” (finalized in July 2010), and “Evaluation of 

Coal Combustion Product Damage Cases: Volume 2: Case Summaries” (finalized in September 

2010). In these reports EPRI provided information that, they claimed, showed that many of 

EPA’s previously identified “proven” damage cases did not meet EPA’s criteria for a damage 

case to be considered “proven.” In response to the 2010 NODA, USWAG submitted a report that 

reviewed the 70 additional damage cases submitted by citizen groups as part of their comments 

on the proposed rule. These reports focused primarily on the degree to which the contamination 

had been contained “on-site” or had migrated off-site of the facility.

In Unit XI, EPA discusses at length all of the comments received and its subsequent 

analysis of the information obtained throughout the rulemaking. In sum, after analyzing all of 

the information submitted by the end of the last comment period EPA has confirmed a total of 

157 cases, both proven and potential, in which CCR mismanagement has caused damage to 

human health and the environment. Although EPA expects that additional damage cases will be 

discovered in response to the installation of the groundwater monitoring systems required by the 

final rule, overall EPA has a significantly better understanding of the extent and nature of the 

damage caused by CCR mismanagement than when the proposed rule was issued. At this stage 

EPA has sufficient confidence in the veracity of the information collected to date to rely on it in 

 

31 EPA also received several additional reports that contained allegations of further damage cases. 

However, because these were submitted after the close of the comment period, EPA did not evaluate these 

damage cases for this rulemaking or otherwise consider the information in those reports. 
Document submitted to conclude E.O.12866 Review

79

making decisions in this rule. 

4. Conclusions

EPA explained in the proposed rule that the decision on whether to retain the Bevill 

exemption is inherently discretionary, in that it ultimately requires the Agency to make a policy 

judgment as to the appropriate balance among the eight statutory factors. Chief among the

several principles that EPA stated would guide its decision was that any action must protect 

human health and the environment. To this end, EPA singled out three key areas of analyses that 

bear directly on that guiding principle: the extent of the risks posed by mismanagement of CCR; 

the adequacy of state programs to ensure proper management of CCR; and the extent and nature 

of damage cases. 

The first of these largely related to the 2010 quantitative risk assessment of the potential 

for contamination to groundwater. During the rulemaking, EPA received information that 

allowed the Agency to resolve two of the four primary uncertainties identified in the proposal. 

The risk assessment has been revised with updated pore water concentration data and with LEAF 

leachate data, and accounts for the potential reduction of contaminants reaching drinking water 

sources due to interception of contamination by surface water bodies. However, two sources of 

uncertainty remain: the potential effect of pollution control technologies on the CCR 

characteristics, and the appropriate IRIS value for arsenic. 

EPA’s risk assessment evaluated current management practices, and generally did not 

attempt to account for or evaluate the potential for future changes in the wastes. While EPA has 

great confidence in the assessment, its ability to definitively resolve this question is therefore 

limited, given the very real potential for significant changes in CCR characteristics and 

constituents in the near future, due to the required installation of pollution control technologies. 
Document submitted to conclude E.O.12866 Review

80

Changes in the CCR characteristics are particularly significant, as the risk assessment concluded 

that one of the parameters most likely to affect the agency’s risk estimates was the characteristic 

of the wastes.

With respect to the second area, EPA is unable to reach any definitive conclusions as to 

whether state regulatory programs are so deficient that the level of federal oversight under 

subtitle C is necessary. Specifically, EPA cannot determine from the available information how 

states, in practice, have implemented regulatory requirements. At this point, only limited 

conclusions are possible.

Clear deficiencies exist in some state regulatory programs, and questions remain with 

respect to others. And many of these concerns exist with respect to programs in states 

responsible for the majority of CCR generation and disposal. However, most state programs, 

although they vary considerably, are not clearly deficient on their face. 

But it is equally clear that exclusive reliance on the regulatory programs as written, 

without any examination of how states have implemented those requirements in practice, would 

not support sweeping conclusions about the overall adequacy of state programs. It is critical to 

ensure that any decision accurately accounts for how the states have exercised their judgment in 

implementing those requirements, before concluding that state programs cannot adequately 

oversee the management of CCR without the degree of federal involvement mandated by subtitle 

C. 

Notwithstanding EPA’s inability to draw conclusions on the overall adequacy of state 

programs, the high degree of variation across state programs strongly supports the need for 

federal requirements to establish a consistent national standard of groundwater and human health 

protection. 
Document submitted to conclude E.O.12866 Review

81

In contrast to the other two areas identified in the proposed rule, while some uncertainty 

remains with respect to the damage cases—namely, whether the 157 identified to date represent 

the total number of damage cases caused by CCR mismanagement, and whether some of the 

“potential” damage cases should be classified as “proven” damage cases—at this point, EPA has 

concluded that the available information provides a sufficient evidentiary base on which 

decisions can be made. In the absence of the necessary information on two of the three critical 

areas, however, EPA cannot reach any final conclusions regarding the appropriate balance 

among the eight statutory factors. Consequently, EPA is also not reaching any final conclusions 

as to whether a damage case is best categorized as “proven” or “potential.” Such a finding is 

relevant only to the Bevill Regulatory Determination. 

However, as discussed in more detail in Unit XI, the damage cases provide extremely 

valuable evidence that is directly relevant to the question of whether and how to regulate CCR 

waste. For example, the damage cases provide “real world” evidence against which to compare 

EPA’s risk modeling estimates, such as evidence regarding the frequency with which particular 

constituents leach into groundwater. They also provide direct evidence regarding specific waste 

management practices at electric utilities, along with the potential consequences of those 

practices. Finally, both the specifics of the damage cases and the fact that they continue to occur 

provide strong evidence of the need for this rule under subtitle D while EPA obtains the 

information that will allow the Agency to make a final Regulatory Determination for these 

wastes. 

Thus, even though EPA is not able to reach a final conclusion on the Regulatory 

Determination for these wastes, the totality of the information in the rulemaking record clearly 

demonstrates that the risks associated with the current management and disposal of CCR remain 
Document submitted to conclude E.O.12866 Review

82

substantial. EPA’s risk assessment concluded that the cancer risks from unlined surface 

impoundments ranged from 3 x 10-4for trivalent arsenic to 4 x 10-5for pentavalent arsenic. 

Noncancer risks from these same units also significantly exceeded EPA’s level of concern, with 

estimates ranging from an HQ of 2 for thallium, to HQs

32 of 4 for molybdenum and 8 for 

trivalent arsenic. The risks associated with unlined landfills were also estimated to be 

significant, with cancer risks of 2 x 10-5for trivalent arsenic. It is important to note that these risk 

numbers are based on national disposal practices. Risks at an individual site may be even higher

based on individual site conditions, waste characteristics, and management practices. EPA’s risk 

assessment identified the potential for higher risks based on different waste pH values and 

management practices. Multiple constituents presented higher risks when considered in waste 

management units that co-dispose both ash and coal refuse at more acidic pHs or FGD wastes at 

more basic pHs. For example, the modeled cancer risks for the co-disposal of ash and coal refuse 

(pH 1.7-8.2) ranged between 10-3for trivalent arsenic to 4 x 10-4for pentavalent arsenic. 

Noncancer risks were similarly high, ranging between and an HQ of 13 for cobalt, and HQs of 

14 for pentavalent arsenic to 26 for trivalent arsenic, based on the ingestion of contaminated 

drinking water. Although this management practice is declining, recent information indicates 

that approximately 5 percent of facilities continue to co-dispose of ash and coal refuse in surface 

impoundments. 

Moreover, EPA’s risk estimates are consistent with the continued damage cases compiled 

through this rulemaking. As discussed in Unit XI, EPA has confirmed that 157 cases of proven 

or potential contamination of groundwater have occurred in states across the nation since the 

initial Regulatory Determination. These damage cases were primarily associated with unlined 

 

32 For more information on HQs please see Unit X. Risk Assessment of this preamble.
Document submitted to conclude E.O.12866 Review

83

units and were most frequently associated with releases of arsenic. While new units are typically 

constructed with composite liners, which under EPA’s current risk assessment adequately 

mitigate the risks, older units still comprise the overwhelming majority of currently operating 

units. EPA’s data show that approximately 63 percent of currently operating surface 

impoundments and landfills are unlined, and thus more prone to leach contaminants into 

groundwater. Analysis of the information from the damage cases also demonstrates that unlined 

surface impoundments typically operate for 20 years before they begin to leak. Most of the 

currently operating surface impoundments are between 20 and 40 years old. 

The age of the units also has implications for their structural stability and the potential for 

catastrophic releases. Of the approximately 735 CCR surface impoundments currently operating 

in the United States, a certain percentage have a great potential for loss of human life and 

environmental damage in the event of catastrophic failure. Based on the information collected 

from EPA’s Assessment Program, 318 surface impoundments have either a high or significant 

hazard potential rating, at least thirteen of which were not designed by a professional engineer. 

Of the total universe of surface impoundments, approximately 186 of these units were not 

designed by a professional engineer. Surface impoundments are generally designed to last the 

typical operating life of coal-fired boilers, on the order of 40 years. However, many 

impoundments are aging; based on the subset of units for which age data were available, 

approximately 195 active surface impoundments exceed 40 years of age; 56 units are older than 

50 years, and 340 are between 26 and 40 years old. In recent years, problems have continued to 

arise from these units, which appear to be related to the aging infrastructure, and the fact that 

many units may be nearing the end of their useful lives. For example, as a result of the 

administrative consent order issued after the December 2008 spill, TVA conducted testing which 
Document submitted to conclude E.O.12866 Review

84

showed that another dike at TVA’s Kingston, Tennessee plant had significant safety deficiencies. 

Collectively, these facts indicate a high likelihood that in the absence of any regulatory action, 

such units will leak in the near future, or are currently leaking, undetected, since groundwater 

monitoring is not installed at many of these older units. Moreover, damage cases continue to 

occur; in response to EPA’s CERCLA 104(e) information request letter, a total of 35 units at 25 

facilities reported historical releases. These range from minor spills to a spill of 0.5 million cubic 

yards of water and fly ash. And as recently as February 2014, CCR slurry was released into the 

Dan River from an inactive surface impoundment in North Carolina. 

All of which demonstrates a compelling need for a uniform system of requirements to 

address these risks without waiting for the information and analyses necessary to complete a 

final Regulatory Determination. EPA will continue to monitor these critical areas, and will 

provide the public with an additional opportunity to comment on any proposed Regulatory 

Determination, prior to issuing a final Regulatory Determination.

B. Final Regulatory Determination Regarding Beneficial Use

EPA generally proposed to retain the May 2000 Regulatory Determination that 

beneficially used CCR did not warrant federal regulation under subtitle C of RCRA. As EPA 

stated in the May 2000 Regulatory Determination, ‘‘In the [Report to Congress], we were not 

able to identify damage cases associated with these types of beneficial uses, nor do we now 

believe that these uses of coal combustion wastes present a significant risk to human health and 

the environment. While some commenters disagreed with our findings, no data or other support 

for the commenters’ position was provided, nor was any information provided to show risk or 

damage associated with agricultural use. Therefore, we conclude that none of the beneficial uses 

of coal combustion wastes listed above pose risks of concern.’’ (See 65 FR 32230.) EPA noted 
Document submitted to conclude E.O.12866 Review

85

that since the original Regulatory Determination, the Agency had found no data or other 

information to indicate that existing efforts of states, EPA, and other federal agencies had been 

inadequate to address the environmental issues associated with the beneficial use of CCR that 

were originally identified in the Regulatory Determination. EPA explained that it had proposed 

this approach in recognition that some uses of CCR, such as encapsulated uses in concrete, and 

use as an ingredient in the manufacture of wallboard, provide benefits and raise minimal health 

or environmental concerns. Consequently, EPA preliminarily concluded that encapsulated uses 

of CCR, which are common in many consumer products, did not merit regulation based on the 

available information. 

However, EPA noted that the issues were more difficult with respect to unencapsulated 

uses of CCR and specifically solicited comment on whether such uses should continue to be 

included as “beneficial use” under the Bevill exemption. EPA explained that unencapsulated 

uses have raised concerns and therefore merited closer attention. For example, the placement of 

unencapsulated CCR on the land, such as in road embankments or in agricultural uses, presented 

a set of issues similar to those that caused the Agency to propose to regulate CCR destined for 

disposal. But the Agency also acknowledged that the amounts and, in some cases, the manner in 

which CCR is used—i.e., subject to engineering specifications and material requirements rather 

than landfilling techniques—are potentially very different from land disposal.

EPA is retaining the original 2000 Regulatory Determination for CCR that is beneficially 

used. EPA has made this determination based on consideration of the available information and 

the RCRA section 8002(n) study factors. 

1. Source and Volume of CCR Generated Each Year 

The American Coal Ash Association (ACAA) conducts a voluntary, annual survey of the 
Document submitted to conclude E.O.12866 Review

86

coal-fired electric utility industry to track the quantities of CCR generated and beneficially used. 

According to the latest survey, the electric utility industry generated nearly 110 million tons of 

CCR in 2012. Approximately 39 million tons of these CCR was identified by ACAA as 

beneficially used in either encapsulated or unencapsulated products. An additional 12.8 million 

tons were placed in mine-fill operations, while the remaining 57.8 million tons were disposed of 

in landfills and surface impoundments (ACAA, 2013).33

2. Present Utilization Practices

Based on the beneficial use rates reported by ACAA, approximately 50 percent of the 

CCR beneficially used on an annual basis falls into two categories: (1) fly ash used as a direct 

substitute for Portland cement during the production of concrete (referred to as “fly ash 

concrete”); and (2) FGD gypsum used as a replacement for mined gypsum in wallboard (referred 

to as “FGD gypsum wallboard”) during use by the consumer. Specifically, the 2012 ACAA 

survey indicates that the largest encapsulated beneficial uses of CCR, by more than a factor of 

two, are fly ash used in “concrete/concrete products/grout” (12.6 million tons) and FGD gypsum 

used in “gypsum panel products” (7.6 million tons).

3. Potential Danger, if Any, to Human Health or the Environment from the Reuse of CCR

The risks associated with the disposal of CCR stems from the specific nature of that

activity; that is, the disposal of CCR in (often unlined) landfills or surface impoundments, with 

thousands, if not millions, of tons placed in a single concentrated location. And in the case of 

surface impoundments, the CCR is managed with water, under a hydraulic head, which promotes 

more rapid leaching of contaminants into neighboring groundwater than conditions in landfills. 

 

33 ACAA (American Coal Ash Association). 2013. 2012 Coal Combustion Product (CCP) Production & 

Use Survey Report. Farmington Hills, MI 48331. Available online at: http://www.acaausa.org/Portals/9/Files/PDFs/revisedFINAL2012CCPSurveyReport.pdf
Document submitted to conclude E.O.12866 Review

87

The beneficial uses identified as excluded under the Bevill exemption for the most part present a 

significantly different risk profile.

a. Encapsulated beneficial uses

An encapsulated beneficial use is one that binds the CCR into a solid matrix that 

minimizes their mobilization into the surrounding environment. Examples of encapsulated uses 

include, but are not limited to: (1) filler or lightweight aggregate in concrete; (2) a replacement 

for, or raw material used in production of, cementitious components in concrete or bricks; (3) 

filler in plastics, rubber, and similar products; and (4) raw material in wallboard production.

Since publication of the proposal, EPA developed a methodology for evaluating 

encapsulated beneficial uses. A copy of the methodology can be found at 

http://www.epa.gov/wastes/conserve/imr/ccps/benfuse_fq.htm. EPA applied this methodology 

to the two largest CCR uses—the use of fly ash as a replacement for Portland cement in concrete, 

and the use of FGD gypsum as a replacement for mined gypsum in wallboard. A complete copy 

of the evaluation can be found at 

http://www.epa.gov/wastes/conserve/imr/ccps/pdfs/ccr_bu_eval.pdf.

The evaluation considered products that meet relevant physical and performance 

standards, that conform to standard design specifications, and that incorporate fly ash and FGD 

gypsum from pollution control devices currently used in the United States. Based on the findings 

of the evaluation, the Agency concluded that environmental releases of constituents of potential 

concern from CCR fly ash concrete and FGD gypsum wallboard during use by the consumer are 

comparable to or lower than those from analogous non-CCR products, or are at or below relevant 

regulatory and health-based benchmarks for human and ecological receptors.

b. Unencapsulated uses 
Document submitted to conclude E.O.12866 Review

88

EPA acknowledged in the proposal that unencapsulated uses generally presented more 

difficult issues than encapsulated uses. CCR can leach toxic metals at levels of concern, so

depending on the characteristics of the CCR, the amount of material placed, how it is placed, and 

the site conditions, there is a potential for environmental concern. However, EPA cannot 

extrapolate from the risk assessments conducted to evaluate the management practices associated 

with CCR landfills and CCR surface impoundments, because the exposure patterns are too 

dissimilar: the amounts and manner involved with beneficial use are very different than the 

thousands, if not millions of tons of CCR that are mounded in a single concentrated location in a 

landfill. And the potential exposures are entirely unlike surface impoundments, where CCR is

managed with water under a hydraulic head, which promotes more rapid leaching of 

contaminants. By contrast “beneficial uses,” even unencapsulated uses, are typically subject to 

engineering specifications, and for certain uses, federal oversight, and material requirements. For 

example, fly ash used as a stabilized base course in highway construction is subject to both 

regulatory standards under the U.S. Department of Transportation (DOT) and the Federal 

Highway Administration (FHA), and engineering specifications, such as the ASTM C 593 test 

for compaction, the ASTM D 560 freezing and thawing test, and a seven day compressive 

strength above 2760 (400 psi). (See 75 FR 35163-35165 for additional examples.) 

In 1999, EPA conducted a risk assessment of certain agricultural uses of CCR, since this 

was considered the most likely to raise human health or environmental concerns.34 EPA 

estimated the risks associated with such uses to be within the range of 1×10-6. These results as 

well as EPA’s conclusion that the use of CCR in agricultural settings was the most likely use to 

 

34 For more information on this risk assessment see EPA’s Notice of Regulatory Determination on Wastes 

from the Combustion of Fossil Fuels (65 FR 32214, May 22, 2000).
Document submitted to conclude E.O.12866 Review

89

raise concerns, caused EPA to conclude that none of the beneficial uses identified in the 2000 

Regulatory Determination warranted federal regulation, because “we were not able to identify 

damage cases associated with these types of beneficial uses, nor do we now believe that these 

uses of coal combustion wastes present a significant risk to human health or the environment.”

(65 FR 32230, May 22, 2000.) 

EPA also noted that beneficially using secondary materials conserves natural resources, 

and can serve as an important alternative to disposal.

4. Documented Cases in Which Damage to Human Health or the Environment from Surface 

Runoff or Leachate has Been Proved 

To date, EPA has seen no evidence of damages from the encapsulated beneficial uses of 

CCR that EPA identified in the proposal. For example, there is wide acceptance of the use of 

CCR in encapsulated uses, such as wallboard, concrete, and bricks because the CCR is bound 

into products. However, as of the date of the proposed rule, seven proven damage cases 

associated with unencapsulated uses have occurred, in which large quantities of unencapsulated 

CCR were used indiscriminately to re-grade the landscape or to fill old quarries or gravel pits. 

The proposed rule discussed two of these cases. (See 75 FR 35147.) The first case was in 

Gambrills, Maryland and involved the disposal of fly ash and bottom ash (beginning in 1995) in 

two sand and gravel quarries. EPA considers this site a proven damage case, because 

groundwater samples from residential drinking wells near the site include heavy metals and 

sulfates at or above groundwater quality standards, and the state of Maryland is overseeing 

remediation. The second case is the Battlefield Golf Course in Chesapeake, Virginia where 1.5 

million yards of fly ash were used as fill and to contour a golf course. Groundwater 

contamination above MCLs has been found at the edges and corners of the golf course, but not in 
Document submitted to conclude E.O.12866 Review

90

residential wells. An EPA study in April 2010, established that residential wells near the site 

were not impacted by the fly ash and, therefore, EPA does not consider this site to be a proven 

damage case. However, due to the onsite groundwater contamination, EPA considers this site to 

be a potential damage case.

During the development of this final rule, EPA obtained information on a comparable 

situation in which large quantities of unencapsulated CCR were placed on the land in a manner 

that presented significant concerns. The AES coal-fired power plant in Puerto Rico lacked 

capacity to dispose of their CCR on-site, and off-site landfills in Puerto Rico were prohibited 

from accepting CCR. In lieu of transporting their CCR off of the island for disposal, AES created 

an aggregate (“AGREMAX”) with the CCR generated at their facility, and used the aggregate as 

fill in housing developments and in road projects. Over 2 million tons of this material was used 

between 2004 and 2012. 

Currently, there is insufficient information to determine whether groundwater has been 

contaminated as a result of this practice, and thus, EPA cannot classify this as either a proven or 

potential “damage case.” Nevertheless, the available facts illustrate several of the significant 

concerns associated with unencapsulated uses. Specifically, the AGREMAX was applied without 

appropriate engineering controls and in volumes that far exceeded the amounts necessary for the 

engineering use of the materials. Inspections of some of the sites where the material had been 

placed showed use in residential areas, and to environmentally vulnerable areas, including areas 

close to wetlands and surface waters and over shallow, sole-source drinking water aquifers. In 

addition, some sites appeared to have been abandoned.

Consistent with the proposed rule, EPA does not consider the practices described in this 

section to be beneficial use, but rather waste management that would be subject to the 
Document submitted to conclude E.O.12866 Review

91

requirements of the final rule. 

5. Alternatives to Current Disposal Methods, the Costs of Such Alternatives, and the Impact 

of Such Alternatives on the Use of Coal and Other Natural Resources 

The beneficial use of CCR is a primary alternative to current disposal methods. And as 

EPA has repeatedly concluded, it is a method that, when performed correctly, can offer

significant environmental benefits, including greenhouse gas (GHG) reduction, energy 

conservation, reduction in land disposal (along with the corresponding avoidance of potential 

CCR disposal impacts), and reduction in the need to mine and process virgin materials and the 

associated environmental impacts.

a. Greenhouse Gas and Energy Benefits

The beneficial use of CCR reduces energy consumption and GHG emissions in a number 

of ways. Three of the most widely recognized beneficial applications of CCR are the use of coal 

fly ash as a substitute for Portland cement in the manufacture of concrete, the use of FGD 

gypsum as a substitute for mined gypsum in the manufacture of wallboard, and the use of CCR 

as a substitute for sand, gravel, and other materials in structural fill. Reducing the amount of 

cement, mined gypsum, and virgin fill produced by substituting CCR leads to large supply chainwide reductions in energy use and GHG emissions. Specifically, the RIA estimates three-year 

rolling average of 53,054,246 MMBtu per year in energy savings and 11,571,116 tons per year in 

GHG (i.e., carbon dioxide and methane) emissions reductions in 2015. This estimate is likely to 

underestimate the total benefits that can be achieved from all beneficial uses. Furthermore, the 

use of fly ash generally makes concrete stronger and more durable. This results in a longer 

lasting material, thereby marginally reducing the need for future cement manufacturing and 

corresponding avoided emissions and energy use.
Document submitted to conclude E.O.12866 Review

92

b. Benefits from Reducing the Need to Mine and Process Virgin Materials 

CCR can be substituted for many virgin materials that would otherwise have to be mined 

and processed for use. These virgin materials include limestone to make cement, and Portland 

cement to make concrete; mined gypsum to make wallboard, and aggregate, such as stone and 

gravel for uses in concrete and road bed. Using virgin materials for these applications requires 

mining and processing, which can impair wildlife habitats and disturb otherwise undeveloped 

land. It is beneficial to use secondary materials—provided it is done in an environmentally sound 

manner—that would otherwise be disposed of, rather than to mine and process virgin materials, 

while simultaneously reducing waste and environmental footprints. Reducing mining, processing 

and transport of virgin materials also conserves energy, avoids GHG emissions, and reduces 

impacts on communities. 

c. Benefits from Reducing the Disposal of CCR 

Beneficially using CCR instead of disposing of it in landfills and surface impoundments 

also reduces the need for additional landfill space and any risks associated with their disposal. In 

particular, the United States disposed of over 57.8 million tons of CCR in landfills and surface 

impoundments in 2012, which is equivalent to the space required of 20,222 quarter-acre home 

sites under eight feet of CCR. 

As discussed in the final rule RIA, the current beneficial use of CCR as a replacement for 

industrial raw materials (e.g., Portland cement, virgin stone aggregate, lime, gypsum) provides 

substantial annual life cycle environmental benefits for these industrial applications. Specifically,

the three-year rolling average of environmental benefits estimated for 2015 includes: (1) 

53,054,246 MMBtu per year in energy savings; (2) 1,661,900 million gallons per year in water 

savings; (3) 11,571,116 tons per year in GHG (i.e., carbon dioxide and methane) emissions 
Document submitted to conclude E.O.12866 Review

93

reductions; (4) 45,770 tons of criteria air pollutant (i.e., NOx, SOx, particulate matter, and CO) 

emissions reductions; and (5) 3,207 pounds of toxic air pollutant (i.e., mercury and lead) 

emissions reductions. All together, the beneficial use of CCR in 2015 is estimated to provide 

over $2.3 billion in annual national environmental benefits. In addition, since EPA estimates 

annual baseline disposal costs of approximately $2.4 billion for the just over 50 percent of tons 

disposed each year, current beneficial use and minefilling also result in annual material and 

disposal cost savings of approximately $2 billion annually.

5. Current and Potential Utilization of CCR 

In 2012, nearly 36 percent (39 million tons) of CCR were beneficially used (excluding 

minefill operations) and nearly 12 percent (12.8 million tons) were placed in minefills. (This 

compares to 23 percent of CCR that were beneficially used, excluding minefilling, at the time of 

the May 2000 Regulatory Determination, and represents a significant increase.)

6. Conclusions

On balance, after considering all of the available information, EPA has concluded that the 

most appropriate approach toward beneficial use is to retain the May 2000 Regulatory

Determination that regulation under subtitle C of the beneficial use of CCR is not warranted. 

EPA has also determined that regulation under subtitle D is generally not necessary for these 

beneficial uses. 

As discussed in the preceding section, the most important of the section 8002(n) factors 

are those relating to the potential risks to human health and the environment. See e.g., Horsehead 

Resource Development Co. v EPA, 16 F.3d 1246, 1258 (DC Cir, 1994) (Upholding EPA’s 

interpretation that wastes resulting from the combustion of mixtures of Bevill-exempt and nonexempt wastes could only retain Bevill-exempt status so long as the combustion waste remained 
Document submitted to conclude E.O.12866 Review

94

of low toxicity); EDF v EPA, 852 F.2d 1316, 1328-1329 (DC Cir. 1988) (Overturning EPA rule 

that included as Bevill exempt, wastes that were not of low toxicity). EPA is adopting this 

Regulatory Determination in recognition that many uses of CCR, such as encapsulated uses in 

concrete, and use as an ingredient in the manufacture of wallboard, provide environmental 

benefits and raise minimal health or environmental concerns. To date, the information available 

does not demonstrate the existence of any risks associated with encapsulated uses of CCR that

merit regulation under either subtitle C or subtitle D of RCRA. 

While there can be some risks associated with unencapsulated uses−for example, the 

placement of unencapsulated CCR on the land, such as in large scale fill operations or in

agricultural uses, depending on the specific site conditions−in general the amounts and, in some 

cases, the manner in which they are used are very different than land disposal. For example, 

agricultural uses involve the placement of inches rather than tons of CCR, and placement of CCR 

in a thin layer rather than mounded in a single concentrated location. In addition, these uses are 

subject to engineering specifications and materials requirements, which will limit the ultimate 

amount of material placed on the land. 

EPA recognizes that several proven damage cases involving the large-scale placement, 

akin to disposal, of CCR have occurred under the guise of ‘‘beneficial use’’— the ‘‘beneficial’’ 

use being the filling up of old quarries or gravel pits, or the re-grading of landscape with large

quantities of CCR. EPA did not consider this type of use as a ‘‘beneficial’’ use in its May 2000

Regulatory Determination, and still does not consider this type of use to be covered by the 

exclusion. Therefore, the final rule explicitly removes these types of uses from the category of 

beneficial use, and from this Regulatory Determination. As discussed in the next section of this 

preamble, EPA has adopted criteria in the final rule to ensure that inappropriate uses that 
Document submitted to conclude E.O.12866 Review

95

effectively are disposal will be regulated as disposal. The final rule expressly defines the 

placement of CCR in sand and gravel pits or quarries as disposal in a landfill. In addition, the

final rule provides that the use of large volumes of CCR in restructuring landscape that does not 

meet specific criteria will constitute disposal. 

While EPA has not definitively concluded that all unencapsulated beneficial uses are 

“safe,” based on the current record for this rulemaking, EPA is unable to point to evidence 

demonstrating that the unencapsulated uses subject to this Determination warrant federal 

regulation. While the absence of demonstrated harm in this instance is not proof of safety, 

neither is the lack of information proof of risk.35 

In this regard, EPA notes that many states have developed beneficial use programs that 

allow the use of CCR, provided they are demonstrated to be non-hazardous materials; and many 

require a site specific assessment before authorizing placement on the land of large amounts of 

unencapsulated CCR. For example, Wisconsin’s Department of Natural Resources has developed 

a regulation (NR 538 Wis. Adm. Code), which includes a five-category system to allow for the 

beneficial use of industrial by-products, including coal ash, provided they meet the specified 

criteria. In addition, the ASTSWMO 2006 Beneficial Use Survey Report states that a total of 34 

of the 40 reporting states, or 85 percent, indicated they had either formal or informal decisionmaking processes or beneficial use programs relating to the use of solid wastes.’’ 

(http://www.astswmo.org/Files/Policies_and_Publications/Solid_Waste/2007BUSurveyReport11

 

35 The Agency is currently developing a Framework to address the risks associated with the beneficial use of 

unencapsulated materials. This Framework is expected to be finalized in 2015. See Unit VI of this notice for more 

information.
Document submitted to conclude E.O.12866 Review

96

-30-07.pdf).36 Because EPA has not identified significant risks associated with the beneficial 

uses covered by this Regulatory Determination, the adequacy of these state programs does not 

factor into EPA’s Determination. Nevertheless, to the extent that that these materials do have the 

potential to pose risk at an individual site, the fact that many states exercise regulatory oversight 

of these materials provides an additional level of assurance. 

Finally, EPA does not wish to inhibit or eliminate the measurable environmental and

economic benefits derived from the use of this valuable material given the current lack of 

evidence affirmatively demonstrating an environmental or health risk. Consequently, EPA is 

confident that the combination of the final rule, EPA guidance, current industrial standards and 

practices, and in many cases, state regulatory oversight is sufficient to address concerns 

associated with the beneficial uses to which this Determination applies. 

V. Development of the Final Rule - RCRA Subtitle D Regulatory Approach 

As previously discussed in Unit II, the authority to develop and promulgate the national 

minimum criteria governing the disposal of CCR in landfills and surface impoundments is found 

under the provisions of sections 1008(a), 4004, and 4005(a) of RCRA (i.e., subtitle D of RCRA). 

These authorities, however, do not provide EPA with the ability to issue permits, require states to 

issue permits, approve state programs to operate in lieu of the federal program, or to enforce any 

of the requirements addressing the disposal of CCR. Consequently, EPA designed the proposed 

RCRA subtitle D option to ensure that the requirements will effectively protect human health and 

the environment within those limitations. The final rule establishes self-implementing 

 

36 EPA has worked with the states to support the development of a national database on state beneficial 

use determinations. Information on the beneficial use determination database can be found on the 

Northeast Waste Management Officials’ Association (NEWMOA) Web site at 

http://www.newmoa.org/solidwaste/bud.cfm. This database helps states share information on beneficial 

use decisions providing for more consistent and informed decisions.
Document submitted to conclude E.O.12866 Review

97

requirements—primarily performance standards--that owners or operators of regulated units can 

implement without any interaction with regulatory officials. 

In developing the subtitle D option for the proposal, EPA considered a number of 

existing programs as relevant models. EPA drew most heavily on the existing 40 CFR Part 258 

program applicable to MSWLFs. While this program does not address CCR disposal in surface 

impoundments, it provided EPA with a general regulatory framework that addressed all aspects 

of disposal in certain land-based units. Given the Agency’s expansive history and experience 

with these requirements, EPA concluded that the part 258 criteria with certain modifications for 

other land-based disposal units (i.e., surface impoundments) represented a reasonable balance 

between ensuring the protection of human health and the environment from the risk of CCR 

disposal and the absence of any regulatory oversight. (See 75 FR 35192-35195.)

EPA also considered that many of the technical requirements developed to specifically 

address the risks from the disposal of CCR as part of the subtitle C alternative would be equally 

justified under a RCRA subtitle D regulatory regime. The factual record—i.e., the risk analysis 

and the damage cases—supporting such requirements was the same, irrespective of the statutory 

authority under which the Agency was operating. Thus, several of the provisions under RCRA 

subtitle D either corresponded to the proposal under RCRA subtitle C, or were modeled after the 

existing subtitle C requirements; for example, EPA proposed the same MSHA-based structural 

stability standards for surface impoundments under the subtitle C and subtitle D options. 

However, because there is no corresponding guaranteed permit mechanism under the RCRA 

subtitle D requirements, EPA also considered the 40 CFR part 265 interim status requirements 

for hazardous waste facilities, which were designed to operate in the absence of a permit. These 

requirements were particularly relevant in developing the requirements for surface 
Document submitted to conclude E.O.12866 Review

98

impoundments since such units are not regulated under 40 CFR part 258. Beyond their selfimplementing design, these requirements provided a useful model because, based on decades of 

experience in implementing these requirements EPA has assurance that these requirements were 

protective for a variety of waste, under a wide variety of site conditions. 

In an effort to ensure that the proposed RCRA subtitle D requirements would achieve the 

statutory standard of “no reasonable probability of adverse effects on health and the 

environment” in the absence of guaranteed regulatory oversight, EPA also proposed to require 

facilities to obtain third party certifications and to provide enhanced state and public notifications 

of actions taken to comply with the regulatory requirements. Specifically, EPA proposed that 

certain technical demonstrations made by the owner or operator be certified by an independent 

registered professional engineer or hydrologist, in order to provide verification and otherwise 

ensure that the provisions of the rule were properly applied. EPA also provided a regulatory 

definition of the term, “independent registered professional engineer or hydrologist,” to identify 

the minimum qualifications necessary to make these certifications. While EPA acknowledged

that relying upon a third party certification was not the same as relying upon a state or federal 

regulatory authority and was not expected to provide the same level of independence as a state 

permit program, the availability of meaningful third party (i.e., independent) verification 

provided critical support that the rule will achieve the statutory standard, as it would provide at 

least some degree of control over a facility’s discretion in implementing the the rule.

As part of the notification requirements, EPA further proposed that all owners and 

operators create and maintain an operating record and publically accessible website, containing 

comprehensive documentation of compliance with the rule. EPA also proposed that owners or 
Document submitted to conclude E.O.12866 Review

99

operators provide notification to the state and the public of third party certifications as well as 

other information documenting actions taken to comply with the criteria of the rule. 

A. The Self- Implementing Approach

While the vast majority of state and industry commenters supported regulating the 

management of CCR under subtitle D of RCRA, a very limited number of commenters favored 

the proposed self-implementing option. Most commenters argued that if the Agency were to 

adopt the proposed subtitle D approach it would most certainly result in parallel and redundant 

regulatory programs for CCR in many states, creating an unworkable situation for industry, as 

well as the state. Some commenters argued that under this dual regulatory approach, an owner or 

operator of a CCR unit could be conceivably be in non-compliance with both a federal 

requirement and an independently administered state regulatory requirement, subjecting the 

owner or operator to both a citizen suit enforcement action in federal court for the alleged 

violation and to a wholly separate enforcement action in state court for violation of the parallel 

state requirement. Commenters argued that this regulatory construct made no sense and would 

waste federal and state judicial resources and company resources, as well as possibly resulting in 

inconsistent federal and state court determinations with respect to an identical regulatory 

requirement. It also could result in duplicative federal and state penalties for essentially the same 

regulatory infraction. 

Commenters further argued that the prescriptive one-size-fits-all approach was overly 

stringent and inflexible and had the potential to greatly disrupt implementation of a state’s 

regulatory programs, which have been tailored to provide for site specific conditions and 

situations. Moreover, commenters argued that because of the many state regulatory programs 

addressing CCR disposal, there would be many instances where state requirements could be in 
Document submitted to conclude E.O.12866 Review

100

conflict with, in addition to, or separate from the federal requirements and it was unclear how 

these differences would be resolved.

Many commenters simply argued that a permitting program similar to that for MSWLFs

was the only viable approach for the regulation of CCR. A significant number of commenters, 

however, proposed various alternative approaches for regulating CCR disposal under subtitle D 

of RCRA. One option would have EPA allow qualified state programs to directly administer the 

subtitle D requirements for CCR when the state regulatory program meets or exceeds the federal 

requirements, thereby minimizing duplicative regulations and avoiding the self-implementing 

“one size fits all” approach contained in EPA's proposal. This option, commenters reasoned, 

could be implemented utilizing a process developed by the Agency for evaluating whether the 

state’s CCR regulations were equivalent to the federal minimum criteria (much like EPA does 

now in the case of MSWLFs under 40 CFR Part 258). Another suggested approach involved 

EPA clarifying that a state can be more restrictive than the federal rule, and that where a state has 

a Subtitle D regulatory program that is more restrictive, the state program and permitting process 

would take precedence over any self-implementation aspects of a final rule. (The proposed rule 

had simply stated that an owner or operator must comply with any other applicable federal, state, 

tribal or local laws or other requirements.) Commenters also proposed a third option, similar to 

the 40 CFR Part 258 program, recognizing that EPA cannot approve state programs in this rule. 

Specifically, 40 CFR part 258 provides a definition for “Director of an approved state” that 

means “the chief administrative officer of a state agency responsible for implementing the state 

permit program that is deemed to be adequate by EPA under regulations published pursuant to 

sections 2002 and 4005 of RCRA.” The commenters suggested that the final rule adopt a similar 

approach by defining a “state permit program” and allowing a state permit program that met the 
Document submitted to conclude E.O.12866 Review

101

definition to approve compliance with a specified regulatory requirement, e.g., landfill design. 

The commenter suggested the following definition: “state permit program means a permit 

program implemented by a state agency that adopts and implements the minimum requirements 

for the disposal of coal combustion residuals outlined in this final rule.” The commenter claimed 

that such an approach should not affect enforcement through citizen suits under RCRA section 

7002 or by EPA under RCRA section 7003. Taking such an approach, commenters reasoned,

would allow states to utilize their own enforcement authority and not rely upon the citizen suit 

authority under RCRA section 7002. Furthermore, allowing states to consider alternative 

approaches to the technical standards may give states an incentive to adopt the minimum 

requirements of the final federal rule into their state permit programs.

As noted, many commenters suggested that EPA could rely on the same combination of 

RCRA statutory authorities, i.e., RCRA sections 4010(c) and 4005(c), to establish controls for 

CCR disposal units that it employed in promulgating federally enforceable subtitle D rules for 

MSWLFs and for non-MSWLFs that receive household hazardous waste and small quantity 

generator waste under 40 CFR Parts 257 and 258. RCRA sections 4010(c) and 4005(c), the 

commenters reasoned, provides EPA that authority because non-hazardous waste CCR disposal 

facilities have the potential to receive household wastes or conditionally exempt small quantity 

generator waste, whether or not such waste is actually received at the CCR disposal facility. 

Commenters contended that the combination of these two provisions could enable EPA to 

promulgate non-hazardous waste rules for CCR that could be directly administered through state 

permitting programs and backed up by direct EPA enforcement powers in those states that fail to 

adequately implement the federal rules. Such an approach, commenters concluded provides the 

Agency with the enforcement authority it desires under a subtitle D regulatory program, while 
Document submitted to conclude E.O.12866 Review

102

enabling states to have a prominent role in the administration of any subtitle D rules, and

preventing the duplication of potentially conflicting federal and state controls. 

Finally, some commenters encouraged EPA to request from Congress the statutory 

authority necessary to propose non-hazardous regulations under subtitle D that could be 

implemented by the states and provide federal enforceability (similar to RCRA’s part 258 

requirements for MSWLFs). Commenters argued that states should be allowed to enforce 

compliance through a traditional permitting system, and that solid waste operating permits are 

critical to ensuring coal ash disposal facilities design, construct, operate and close their waste 

facilities safely. Permits are important because they can dictate the use of specific operating 

practices and control technologies that may be essential for minimizing releases. Permits also 

provide an important enforcement vehicle, as well as a process by which the public can be 

informed and participate in the siting, operation and closure of the waste disposal unit. 

While the Agency appreciates commenters’ attempts to craft alternative approaches to 

address the limitations in the proposed self-implementing subtitle D option, EPA has not 

“chosen” to design standards under subtitle D that are self-implementing. The sections of RCRA 

that are currently applicable to CCR – sections 1008(a), 4004(a), and 4005(a)--only authorize the 

Agency to establish minimum national criteria that apply to “facilities.”

As previously discussed, these provisions do not authorize EPA to require that facilities 

obtain a permit from EPA or a state. The fact that section 4004(a) does not contain any provision 

that either expressly requires a permit to manage waste, such as in section 3005, or that requires 

states to adopt a permit program, such as in section 4004(c)(1), provides strong evidence that 

Congress did not authorize EPA to impose such a requirement on facilities managing solid 

waste. Compare 42 U.S.C. §§ 6925(a), 6944(a), and 6945(c)(1). This is further confirmed by the 
Document submitted to conclude E.O.12866 Review

103

fact that Congress thought it necessary to expressly add provisions to require state permit 

programs in 4010(c) and 4005(c). And the fact that the HSWA provisions are limited to two 

specifically enumerated types of units provides further evidence that Congress intended to 

authorize EPA to require permits only for these units. 

The restriction that the criteria apply only to “facilities” also means that EPA cannot 

establish any requirements on states or state programs, either directly or indirectly. This means, 

for example, that EPA cannot adopt a regulation that restricts certain provisions to those “state 

permit programs” that meet EPA requirements, as one commenter suggested, since this would 

indirectly regulate state programs—leaving aside that EPA never proposed anything of the sort. 

This also means that EPA cannot require a facility to obtain state approval, as this not only 

presupposes the existence of a state permit program, but also that the state will approve the 

facility action on the basis of EPA's criteria. EPA cannot condition a facility’s compliance on 

actions beyond its control.

However, these provisions restrict EPA’s authority only. The legislation is clear that these 

are minimum requirements only, and without preemptive effect; states may therefore impose 

more stringent requirements, including the requirement that CCR facilities obtain a permit. This 

is also wholly consistent with longstanding EPA interpretations. See 44 FR 53438, 53439 

(September 13, 1979) (“the standards established in the criteria constitute minimum 

requirements. These criteria do not preempt other State and Federal requirements. Nothing in the 

Act precludes the imposition of additional obligations under authority of other laws on parties 

engaged in solid waste disposal.”); see also 44 FR 45066 (July 31, 1979) (“EPA establishes only 

‘minimum’ requirements under this portion of the Act which should not prevent States from 

developing broader programs or stricter standards under authority of State law.”). States may 
Document submitted to conclude E.O.12866 Review

104

also incorporate the federal requirements into state law—whether through revisions to existing 

legislation or regulation, or through incorporating them into any permits issued to CCR facilities. 

Such an approach would also resolve commenters’ concerns about the potential for “parallel and 

redundant regulatory programs.” 

While subtitle C and 4005(c) provide for state oversight on rule implementation and 

allow approved state requirements to operate in lieu of federal criteria, the Agency lacks the 

authority to do so under the subsections of RCRA currently applicable to CCR. The provisions 

applicable to solid waste—sections 1008(a)(3), 4003, 4004(a) and 4005(a)—establish a 

regulatory structure that differs in key respects from those established under subtitle C and for 

MSWLFs under section 4005(c). Under subtitle C and section 4005(c), Congress required EPA 

to establish federal criteria that will serve as national minimum standards, which is comparable 

to the authority under section 4004(a). But subtitle C and section 4005(c) also include detailed 

provisions governing both the state implementation of those requirements and the relationship 

between the federal requirements and the state programs that implement them. No comparable 

provisions appear in either section 4004(a) or section 4003, which governs the approval of state 

solid waste management plans. And the consequences of these omissions are significant. 

Subtitle C of RCRA contains several provisions that establish the relationship between 

the federal program and state requirements; these include provisions authorizing EPA to approve 

state programs and to retain a direct role in the implementation of the federal minimum 

requirements, whether through continued oversight of state implementation or direct 

implementation of the regulations. See, 42 U.S.C. §§ 6926, 6928(a)(2), and 6929. For purposes 

of this issue, the most critical of these is the explicit direction in section 3006 that authorized 

state programs “operate in lieu of the Federal program.” 42 U.S.C. § 6926(b), (c)(1). See also 42 
Document submitted to conclude E.O.12866 Review

105

U.S.C. § 6929 (prohibiting the adoption of less stringent state requirements than those in EPA 

regulations, and authorizing states to establish more stringent requirements). 

The provisions for MSWLFs under section 4005(c) are less detailed, but establish a 

similar regulatory structure. Section 4005(c)(1) expressly directs the states to "adopt and 

implement a permit program or other system of prior approval and conditions,” for covered 

facilities in order to implement federal requirements established for such facilities. 42 U.S.C. § 

6945(c)(1). The statute directs EPA to determine the adequacy of such programs, and directs 

EPA to enforce the federal requirements in states that have not adopted an adequate program. 42 

U.S.C. § 6945(c)(1)(C), (2). While less detailed than the provisions under subtitle C, section 

4005(c) establishes a system that is equally predicated on mandated implementation by a state 

regulatory authority of the federal requirements, rather than the potential coexistence of two 

separate regulatory systems. 

The absence of any similar provisions in the “solid waste” provisions of subtitle D 

demonstrates that Congress intended to create a different regulatory structure. EPA’s role under 

sections 1008(a)(3) and 4004(a) is to establish minimum criteria to determine which facilities 

“shall be classified as sanitary landfills and which shall be classified as open dumps,” and to 

encourage states to use the criteria as a part of their solid waste management planning. Under 

this regulatory structure, Congress intended that the federal requirements apply directly to 

facilities and operate independent of state involvement, unless the state chooses to do otherwise. 

The ability to approve state SWMPs under section 4003 does not alter this relationship. Indeed, 

the fact that Congress thought it necessary to revise section 4005 to include the specific 

provisions in subsection (c) confirms that Congress did not believe such authority already existed 

under sections 4003 and 4004. 
Document submitted to conclude E.O.12866 Review

106

Approval of a state’s solid waste management plan pursuant to section 4003 qualifies the 

state to receive federal funds (no longer available) and authorizes the state to issue compliance 

schedules; but unlike under section 3006 or 4005(c), an authorized plan does not affect the 

federal minimum standards themselves, or authorize states to do so. Section 4003 contains 

nothing that explicitly or implicitly authorizes state requirements to operate “in lieu of” the 

federal requirement as a consequence of EPA approval of the state plan. The closest analogue is 

that states with an approved plan may establish a “timetable or schedule” to bring existing open 

dumps into compliance with the federal requirements; but notably, Congress only authorized the 

state to modify the timeframes by which such facilities must be in compliance, not the 

substantive requirements themselves. 42 U.S.C. § 6945(a).

The combination of this regulatory structure and the need to demonstrate that the final 

rule achieves section 4004(a)’s protectiveness standard based on the record at the time the rule is 

promulgated also effectively limits EPA’s ability to establish the kind of regulatory provisions 

commenters have requested (i.e., establish an alternative that allows a State permit program to 

approve a less stringent technical requirement based on site specific conditions). Because as 

discussed in Unit IV.A, EPA is currently unable to reach a conclusion regarding the adequacy of 

state programs, EPA cannot demonstrate that such an alternative would meet the section 4004(a) 

standard. And in the absence of a mandatory mechanism for subsequent public involvement and 

review, which would create decisions with their own record, subject to judicial review in their 

own right, the lack of such information is dispositive. 

With respect to the proposal to rely on RCRA sections 4010(c) and 4005(c) authorities, 

EPA also disagrees that this is a viable option. As the comment appears to acknowledge, 

construing sections 4010(c) and 4005(c) to apply to CCR disposal units on the basis that they 
Document submitted to conclude E.O.12866 Review

107

could potentially receive conditionally-exempt small quantity generator waste is inconsistent 

with EPA’s longstanding interpretation of those sections. EPA directly addressed this issue 

nearly 20 years ago in the preamble for EPA’s final rules at 40 CFR 257, Subpart B. That 

discussion is reproduced here in its entirety: 

The proposed rule was written to provide that only those non-municipal nonhazardous waste disposal units which meet the requirements in §§ 257.5 through 257.30 

"may receive" CESQG waste, as required by RCRA section 4010(c). Any non-municipal 

non-hazardous waste disposal unit that did not meet the proposed requirements may not 

receive CESQG hazardous wastes. The proposal was written to apply to non-municipal 

non-hazardous waste disposal units that receive CESQG waste for storage, treatment, or 

disposal, including such units as surface impoundments, landfills, land application units 

and waste piles. The regulatory definition of the term "disposal" cover all placement of 

wastes on the land. See 40 CFR 257.2.

Several commenters addressed the Agency's interpretation of the statutory language 

"may receive". One commenter supported the Agency's decision to limit the proposed 

regulatory requirements to only those non-municipal non-hazardous waste disposal units 

that receive CESQG wastes. Another commenter, however, stated that a closer reading of 

Section 4010(c) reveals that Congress was not only concerned about modifying the criteria 

for "facilities that may receive hazardous household wastes or hazardous wastes from small 

quantity generators * * *" but also for "facilities potentially receiving such wastes." 

According to the commenter, the "may receive" clause of the first sentence in Section 

4010(c) merely refers to whether a facility may legally receive CESQG waste for disposal. 

The "potentially receiving such wastes" clause of the third sentence of Section 4010(c) 
Document submitted to conclude E.O.12866 Review

108

refers to the actual potential for such facilities to receive CESQG wastes. The potential for 

CESQG waste to be disposed of at many types of industrial D landfills is high even with 

the proposed prohibition under § 261.5. It is the "potentially receiving" clause that 

specifically commands the Agency to promulgate provisions for all industrial facilities that 

could potentially receive CESQG wastes.

EPA disagrees with the commenter's interpretation of the statutory language in 

RCRA section 4010(c). More specifically, for a number of reasons, the Agency does not 

believe that the statutory language cited by the commenter evidences congressional intent 

that the revised criteria being promulgated in this rule should address disposal of solid 

waste in all industrial disposal facilities. First, EPA believes that the commenter errs by 

focusing only on the "facilities potentially receiving" language in the last sentence of 

section 4010(c). If one reviews this language together with the statutory language in RCRA 

section 4010(a), it is clear that Congress did not intend for the revised criteria being 

promulgated in this rule to apply to all industrial landfills. 

“RCRA section 4010(a) required EPA to conduct a study of the then existing 

guidelines and criteria issued under RCRA sections 1008 and 4004 which were applicable 

to "solid waste management and disposal facilities, including, but not limited to landfills 

and surface impoundments." 42 U.S.C. § 6949a(a). This statutory language does indeed 

suggest that EPA was to study a wide range of solid waste disposal facilities, including

industrial landfills. (As the commenter stated, because the information on industrial 

disposal facilities was quite limited, EPA's report to Congress did focus on municipal 

landfills.)
Document submitted to conclude E.O.12866 Review

109

However, the statutory language in section 4010(c) directing EPA to promulgate a 

rule revising the criteria in 40 CFR Part 257 limits the rule's applicability only to those 

facilities which may receive hazardous household waste or small quantity generator waste. 

42 U.S.C. 6949a(c). If Congress had intended the revised criteria under section 4010(c) to 

apply to all solid waste disposal facilities, including industrial landfills and surface 

impoundments, it clearly could have done so by enacting language similar to that already 

used in section 4010(a).

Secondly, the legislative history of RCRA section 4010 suggests that Congress 

expressly rejected a provision that would have required rules to be promulgated under 

section 4010(c) to apply to the entire universe of RCRA Subtitle D solid waste disposal 

facilities. Indeed, the House version of section 4010 would have required EPA to 

promulgate revised guidelines and criteria such that they would be applicable to all "solid 

waste management and disposal facilities, including, but not limited to landfills and surface 

impoundments * * *." H.R. 2867, section 30, 98th Cong., 1st Sess. (as introduced in the 

Senate on November 9, 1983). However, the Conference Committee instead adopted a 

Senate amendment which limited the scope of the revised criteria to those facilities that 

may receive hazardous household waste or small quantity generator waste. H. Rept. No. 

98-1133, 98th Cong., 2d Sess., at 116-117.

Another indication that RCRA section 4010(c) was not intended to cover the entire 

universe of solid waste disposal facilities is the fact that subsequent to the enactment of 

section 4010(c) (as part of the Hazardous and Solid Waste Amendments in 1984), a number 

of bills were introduced in Congress which would have either authorized or required EPA 

to issue additional regulations that would address all disposal facilities receiving industrial 
Document submitted to conclude E.O.12866 Review

110

waste as opposed to addressing those which may receive CESQG waste as stated in Section 

4010(c). See, e.g., H.R. 3735, "Waste Materials Management Act of 1989," section 324 

(would have required EPA to promulgate standards for the management of industrial solid 

waste) (Luken Bill); S. 1113, "Waste Minimization and Control Act of 1989," section 204 

(would have required EPA to promulgate requirements for facilities that manage different 

types of industrial waste) (Baucus Bill). Neither of these provisions (although neither was 

enacted) would have been necessary if RCRA section 4010(c) required EPA to promulgate 

revised criteria for all types of industrial disposal facilities.

This same commenter cites to language in both the Report to Congress (as provided 

for in RCRA section 4010(b)) and the MSWLF rulemaking to suggest that EPA 

acknowledged that all industrial landfills, even those not receiving CESQG waste, should 

fall within the scope of this rule. EPA acknowledges that it expressed a concern about the 

potential risks that industrial solid waste disposal facilities might pose; however, EPA 

indicated that it did not have the level of information necessary to conduct a rulemaking 

for such disposal facilities. At the time of issuing the final MSWLF rule, EPA indicated 

that it would attempt to study these facilities to gain a better understanding of the risks that 

they may pose. See 56 FR 51000 (Oct. 9, 1991).

After investigating available information in more detail, it became clear that of all 

industrial solid waste disposal facilities, only construction and demolition and off-site 

commercial facilities typically receive CESQG waste. As discussed in the proposed rule, 

recent information and discussions with the relevant industries indicate that on-site 

industrial disposal facilities (which make up the vast majority of industrial disposal 

facilities) generally do not receive CESQG waste. However, the commenter should be 
Document submitted to conclude E.O.12866 Review

111

aware that EPA has drafted the rule such that it will apply to such industrial on-site facilities 

if they receive CESQG waste. See sections 257.5(a) (1) and (3).” 

(See 61 FR 34252, 34254-55 (July 1, 1996).)

The commenter makes essentially the same argument based on the same language in 

4010(c) that EPA rejected in the above discussion. The commenter provided no legal analysis 

that contravenes the bases for EPA’s interpretation of Subtitle D. EPA thus declines to reopen or 

reconsider this interpretative question. EPA also notes that in any case, information in its record 

for this rulemaking indicates that CCR landfills or surface impoundments do not actually or 

potentially receive CESQG wastes. 

Nevertheless, EPA recognizes that this regulatory structure gives rise to legitimate 

concerns about the potential for duplicative or conflicting state and federal regulatory systems. 

EPA has adopted measures to address these concerns within the confines of the regulatory 

structure that Congress established in subtitle D. First, EPA has made every effort to ensure that 

the final rule does not establish any requirements that truly conflict with existing state programs. 

To clarify, this does not mean that the requirements are necessarily the same, but rather that it is 

possible to comply with both federal and state requirements simultaneously. Or in other words, 

compliance with the more stringent standard—whether federal or state—will ensure compliance 

with the less stringent. Based on the comments received, EPA is aware of no example of a 

situation in which truly conflicting requirements will exist. Second, as discussed, these 

regulations do not constrain or direct state action. States can impose more stringent or different 

requirements, such as requiring a permit. Nor does the regulation require the state to enforce the 

federal requirements; even with promulgation of the final rule, the decision to bring an action 

under section 7002 remains entirely within the state’s discretion. Third, as discussed in greater 
Document submitted to conclude E.O.12866 Review

112

detail in Unit IX, EPA has developed a number of measures to clarify the relationship between 

an individual state program, or particular requirements, and the federal criteria. Specifically, for 

those states that choose to submit revised state SWMPs that incorporate the federal criteria, EPA 

intends to rely on the existing processes in 40 CFR Part 256 relating to approval of state solid 

waste management plans. EPA expects that approval of a state solid waste management plan, 

while it cannot prevent a citizen group from filing a lawsuit, will carry substantial weight in any 

court proceeding charged with determining whether compliance with state requirements 

constitutes compliance with the federal criteria. 

 

B. Enforceability of the Subtitle D Approach 

Numerous commenters raised concern that reliance on a RCRA citizen suit as the basic 

enforcement mechanism to address non-compliance with the CCR requirements presents 

environmental justice concerns. Commenters argued that as a practical matter, this selfimplementing approach would result in unenforced regulations affecting neighborhoods where 

environmental, legal, and technical services are unavailable or difficult to obtain. Commenters 

stated that it would be highly unreasonable for EPA to place the burden of enforcement of the 

CCR regulations on citizens, arguing that it is EPA’s duty to make sure federal regulations

protecting human health and the environment are enforced fairly and effectively, and that 

enforcement by citizen suits puts an unacceptable burden on low income populations located 

near these facilities. Commenters contended that environmental justice communities were the

least likely to mount a serious challenge to the industry because low income people are often less 

well-educated, have less access to computers and internet technology, less knowledge of how to 

access and interpret environmental data, and are the least likely to have the resources for a time 
Document submitted to conclude E.O.12866 Review

113

consuming legal battle. Commenters argued that given the high number of damage cases in this 

industry, it was clear that the industry cannot police itself and neither can state governments. For 

these reasons, commenters asserted that the regulations and the enforcement must come from the 

federal level. 

Conversely, other commenters were encouraged by the opportunity to enforce the rule

through citizen suits, stating that it would result in very effective regulation since citizens have 

shown no reluctance to challenge companies that they believe are not responsibly following 

environmental regulations. Similarly, other commenters noted that other incentives existed to 

comply with the regulations, including the possibility of state and third party litigation (for both 

regulatory compliance and actual damages), and the requirements of investors, lenders, and 

insurers to demonstrate compliance with environmental requirements, i.e., investors and lenders 

typically condition capital investments and loans on environmental compliance. Commenters 

also noted that incentives to comply were created by environmental insurance policies, which 

“invariably exclude damage claims arising from non-compliance from covered events” as well as 

typical corporate policies that call for environmental compliance as a standard operating 

procedure.

Other commenters focused on the role of the professional engineer in the selfimplementing framework, arguing that EPA is requiring the certifying professional to 

inappropriately take on a quasi-regulatory and enforcement role which places the certifying 

professional at great risk of being subject to nuisance lawsuits from project opponents, creating a 

scenario where some professionals may decline to be involved in such reviews. Still other 

commenters argued with EPA’s basic premise that the RCRA subtitle D program lacks 

enforceability. Commenters contended that EPA’s concerns about the lack of direct federal 
Document submitted to conclude E.O.12866 Review

114

enforcement authority failed to recognize the significant enforcement opportunities available 

under existing law, namely the "imminent and substantial endangerment authority" under RCRA 

section 7003 to take action against any CCR unit that posed a risk to human health and the 

environment, as well as, the imminent and substantial endangerment authorities under CERCLA, 

as well as other federal authorities, including the federal Clean Water Act, to address 

circumstances where a CCR unit posed a threat. 

EPA acknowledges that the lack of federal enforcement under Subtitle D presents 

challenges. However, as discussed above, issuing minimum national standards under the 

authority that is currently applicable to CCR (i.e., subtitle D) is significantly more protective 

than the current federal standards in part 257 that apply to these wastes. It is more consistent with 

EPA’s obligations under RCRA to put in place the additional protections that, based on the 

information currently available, are needed to protect health and the environment. As part of 

those requirements, EPA has developed a number of provisions designed to facilitate citizens to 

enforce the rule pursuant to RCRA section 7002. Chief among these is the requirement to 

publicly post monitoring data, along with critical documentation of facility operations, so that the 

public will have access to the information to monitor activities at CCR disposal facilities. 

Moreover, as noted elsewhere, a state seeking EPA’s approval for a State Solid Waste 

Management Plan would be required to conduct a public comment process to avail itself of the 

benefits of an EPA’s approval. 

EPA also agrees that the Agency retains the authority to bring an action under RCRA 

section 7003, as well as other statutes, when the facts support the necessary findings. However, 

an action under section 7003 does not enforce the requirements of this rule. Certainly, EPA 

believes that the failure to comply with the requirements of the rule increases the probability that 
Document submitted to conclude E.O.12866 Review

115

an imminent and substantial endangerment may arise, but the fact that a facility has not complied 

with one or more of the requirements of this rule does not per se establish that a section 7003 

order is warranted.

The Agency also acknowledges that the self-implementing frameworks could potentially 

place certifying professionals at risk for lawsuits; several of the performance standards in the 

proposed rule were adopted from part 258, which were designed to operate in the context of an 

approved state program, under the oversight of a state regulatory authority, rather than a purely 

private entity. In part due to this concern, the Agency has re-evaluated the performance standards 

throughout the final rule, and has revised them where necessary to ensure that the requirements 

are sufficiently objective and technically precise that a qualified professional engineer will be 

able to certify that they have been met. 

C. Reliance on Certification by Independent Qualified Professional Engineers

As previously discussed, the majority of commenters were highly skeptical of a 

regulatory approach that substituted state oversight with an owner or operator hiring a consultant 

or professional, i.e., an independent registered professional engineer or hydrologist, to certify 

compliance with a federal regulatory requirement and posting that information on an internet 

site. More specifically, commenters were concerned that relying almost entirely on professional 

certifications for ensuring regulatory compliance did not seem like a reliable way to provide for 

protection of human health and or the environment. 

As explained in Unit IV.A, EPA is issuing national minimum criteria under subtitle D to 

put in place the technical requirements the Agency has determined are necessary to protect 

human health and the environment from the disposal of CCR in surface impoundments and 

landfills, while the Agency completes its Bevill Determination. EPA is relying on the 
Document submitted to conclude E.O.12866 Review

116

certification in this context to partially compensate for one of the more significant limitations 

under the authorities currently applicable to CCR: the lack of any guaranteed regulatory 

oversight mechanism. However, EPA disagrees that the rules rely "almost entirely" on 

professional engineers to protect human health and the environment. The final rule relies on 

multiple mechanisms to ensure that the regulated community properly implements requirements 

in this rule. As one part of this multi-mechanism approach, owners or operators must obtain 

certifications by qualified individuals verifying that the technical provisions of the rule have 

been properly applied and met. However, a more significant component supporting EPA's 

determination that the technical requirements will achieve the level of protection required under 

section 4004(a) is the performance standards that the rules lay out. These standards impose 

specific technical requirements, and, even where they provide flexibility, will operate to 

significantly constrain the facility's activities and discretion. The certifications required by the 

rule supplement these technical requirements, and while they are important, they are not the sole 

mechanism ensuring regulatory compliance.

The rule also contains a number of provisions requiring the owner or operator to 

document their compliance with the rule’s technical requirements, and to post those documents 

on a publically available website in a timely and transparent manner. The rule also requires 

owners or operators to notify State Directors of numerous actions, including that certified 

demonstrations have been completed. This transparency will facilitate citizen and state oversight 

and overall enforcement of the requirements. Finally, the rule establishes specific timeframes by 

which these actions must occur, including timeframes by which facilities must document

compliance with the various technical requirements in the rule. Timeframes have been 

established for: (1) technical compliance demonstrations made by the owner or operator; (2) 
Document submitted to conclude E.O.12866 Review

117

certifications made by a qualified professional engineer verifying the technical accuracy and 

veracity of the compliance demonstration; (3) notifications made to the State Director; (4) 

submittals (e.g., data, reports and other documentation) to the operating record; and (5) postings 

to the owner or operator’s publicly accessible internet site. Further details pertaining to all of 

these requirements can be found in the Recordkeeping, Notification, and Posting of Information 

to the Internet section of the regulations published in this rule. 

1. Changes to the Definition of Independent Registered Professional Engineer or Hydrologist

EPA proposed to define “independent registered professional engineer or hydrologist” to 

mean a scientist or engineer who is not an employee of the owner or operator of a CCR landfill 

or CCR surface impoundment, who has received a baccalaureate or post-graduate degree in the 

natural sciences or engineering, and who has sufficient training and experience in groundwater 

hydrology and related fields as may be demonstrated by state registration, professional 

certifications, or completion of accredited university programs that enable that individual to 

make sound professional judgment regarding the technical information for which a certification 

under this subpart is necessary.

Many comments were received on the definition. Some commenters agreed with the 

proposed definition, but most commenters argued that significant changes were needed. These 

changes included removing the requirement that the engineer be “independent,” adding the word 

“qualified,” and limiting the ability to make certifications to “licensed” professional engineers. 

Still other commenters felt that EPA should broaden the qualifications beyond a professional 

engineer or hydrologist, to include geologists, hydrogeologists, groundwater scientists or “other 

qualified environmental professionals” among the individuals able to certify regulatory 

demonstrations. 
Document submitted to conclude E.O.12866 Review

118

By far the issue receiving the most comment was whether the Agency should require a 

professional engineer to be “independent.” Commenters disagreed with EPA that the certification 

must be made by an independent registered professional engineer (i.e., not an employee of the 

owner/operator of the CCR unit). Commenters argued that most utilities employ a number of 

professional engineers that typically possess the most relevant experience and knowledge about 

the unit, and that company-employed engineers and hydrologists were in a much better technical 

position to certify technical provisions of the rule were being met. Furthermore, commenters 

asserted that these professionals would be subject to the same state registration and licensing 

requirements as those not employed by the facility and would have an equally strong incentive to 

maintain their licenses in good standing as those that are independent of the utility. These 

commenters also pointed to several EPA rulemakings in which EPA allowed “qualified”

professional engineers to make the kind of certifications contemplated by this rulemaking, 

without requiring that they be “independent.” Commenters also contended that state licensing 

and registration programs help to ensure that all professionals exercise proper judgment or 

“independence” regarding the operation of CCR landfills and CCR surface impoundments. 

Similarly, commenters claimed that a professional engineer without the required expertise would 

refuse to make any certifications for which they were not qualified. Some commenters suggested 

that EPA provide some criteria requiring demonstrated experience and training. Commenters 

also took issue with the fact that the definition focused entirely on groundwater hydrology and 

failed to include training or experience in other areas that would also be necessary to effectively 

certify specific technical criteria of the rule (e.g., structural integrity, composite liner design).

The definition EPA proposed for “independent registered professional engineer or 

hydrologist,” focused on three components that were intended to define the minimum 
Document submitted to conclude E.O.12866 Review

119

qualifications necessary to independently verify that a specific technical standard was met and to 

provide sufficient objectivity to reduce the opportunity for abuse. These components were: (1) 

the individual was a scientist or engineer by academic training or education; (2) the individual 

was not an employee of the owner or operator of the CCR disposal unit; and (3) the individual 

had sufficient training in groundwater hydrology or related fields. The proposed definition did 

not require the individual to be licensed professional engineer or hydrologist; instead the Agency 

prohibited the individual providing the certification from being an employee of the owner or 

operator of the CCR unit, reasoning that this requirement would provide some degree of 

independent verification of facility practices.37 The Agency stated that the availability of 

meaningful independent verification was critical to EPA’s ability to conclude that the

performance standards laid out in the proposed rule would meet the RCRA section 4004 

protectiveness standard.

In the course of developing this final rule, the Agency concluded that it needed to better 

define the connection between the technical requirements of the rule and the technical 

qualifications an individual must possess to certify the demonstrations being made by the owner 

or operator of the CCR disposal unit. In doing so, the Agency looked for direction in the 

following rules, the “Resource Conservation and Recovery Act (RCRA) Burden Reduction 

Initiative” (71 FR 16826, April 4, 2006) and the “Oil Pollution Prevention and Response; Non-

 

37 While the definition did not require the independent registered professional engineer or hydrologist to 

be licensed, the preamble did state that EPA expects that professionals in the field will have adequate 

incentive to provide an honest certification, given that the regulations require that the engineer not be an 

employee of the owner or operator of the CCR landfill or CCR surface impoundment, and that they 

operate under penalty of losing their license, implying that the professional was, in fact, licensed. This 

narrative and the title of independent registered professional engineer caused many commenters to 

assume that the certifiers indeed had to be licensed professional engineers. (See 75 FR 35194, June 21, 

2010.)
Document submitted to conclude E.O.12866 Review

120

Transportation-Related Onshore and Offshore Facilities rule (67 FR 47042, July 17, 2002). In 

both of these actions, the Agency had come to similar conclusions. First, that professional 

engineers, whether independent or employees of a facility, being professionals, will uphold the 

integrity of their profession and only certify documents that meet the prescribed regulatory 

requirements; and that the integrity of both the professional engineer and the professional 

oversight of boards licensing professional engineers are sufficient to prevent any abuses. (For an 

example see: 67 FR 47084, July 17, 2002.) And second, that in-house professional engineers 

may be the persons most familiar with the design and operation of the facility and that a 

restriction on in-house professional certifications might place an undue and unnecessary 

financial burden on owners or operators of facilities by forcing them to hire an outside engineer. 

Reviewing these other regulatory actions and the Agency’s rationale for making its 

decisions, has led the Agency to a similar conclusion with regard to this rule -- that it is 

unnecessary to require the individual making certifications under this rule to be “independent.”

Thus the final rule does not prohibit an employee of the facility from making the certification, 

provided they are a professional engineer that is licensed by a state licensing board. The personal 

liability of the professional engineer provides strong support for both the requirement that 

certifications must be performed by licensed professional engineers, and for removing the 

requirement that the engineer be "independent." 

While other commenters argued that the word “independent” should be retained because 

an independent review and certification avoids any potential of conflict of interest, the Agency is 

convinced that an employee of a facility, who is a qualified professional engineer and who has 

been licensed by a state licensing board would be no more likely to be biased than a qualified 

professional engineer who is not an employee of the owner or operator. Moreover, it is not clear 
Document submitted to conclude E.O.12866 Review

121

that an in-house engineer faces a greater economic temptation than an independent engineer 

seeking to cultivate an ongoing relationship with a client. EPA has concluded that the programs 

established by state licensing boards provide sufficient guarantees that a professional engineer, 

regardless of whether he/she is “independent” of the facility, will give a fair technical review. 

As an additional protection, the Agency has re-evaluated the performance standards 

throughout the final rule to ensure that the requirements are sufficiently objective and technically 

precise that a qualified professional engineer will be able to certify that they have been met. 

The Agency agrees with concerns that a professional engineer may not be qualified to 

address all the varied aspects of CCR landfill and CCR surface impoundment design, and has 

amended the definition to clarify and strengthen the qualifications of the individual authorized to 

certify the technical demonstrations under the rule. In the proposed rule, the Agency did not 

require an independent registered professional engineer to be licensed, only that they be an 

engineer or hydrologist who had received a baccalaureate or post graduate degree in the natural 

sciences with training and experience in groundwater hydrology or a related field. While the 

term “independent registered professional engineer or hydrologist” conveyed to some 

commenters that the individual was in fact “licensed,” the definition in the proposal did not 

require it. Furthermore, as noted by commenters, the proposed definition focused primarily on 

hydrogeology expertise and did not include training and experience qualifications necessary to 

accurately certify some of the requirements being promulgated in the rule, e.g., landfill and 

surface impoundment design and construction, structural stability assessments, analysis of 

unstable areas. In reviewing this proposed requirement, the Agency has determined that 

specifying exact qualifications and or experience for the professional engineer is neither

necessary nor practical, given the range of technical specifications that will require certification. 
Document submitted to conclude E.O.12866 Review

122

EPA has therefore adopted a more succinct requirement focused on the professional engineer’s

qualifications to perform the task or certification. 

In making this change, the Agency was again strongly influenced by the “Resource 

Conservation and Recovery Act (RCRA) Burden Reduction Initiative” rule. (See 71 FR 16826, 

April 4, 2006.) In that rule, EPA amended the majority of RCRA provisions requiring the 

certification of an “independent, qualified, registered, professional engineer” to substitute the 

phrase, a “qualified professional engineer,” reasoning that a requirement for a qualified 

professional engineer maintains the most important components of any certification requirement:

(1) that the engineer be qualified to perform the task based on training and experience; and (2) 

that she or he be a professional engineer licensed to practice engineering under the title 

Professional Engineer which requires following a code of ethics with the potential of losing 

his/her license for negligence (see 71 FR 16868.) 

In the “Burden Reduction Rule”the Agency concluded that a professional engineer is able 

to give fair and technical review because of the oversight programs established by the state 

licensing boards that will subject the professional engineer to penalties, including the loss of 

license and potential fines if certifications are provided when the facts do not warrant it. In fact, 

this personal liability of the professional engineer is one of the primary reasons that commenters 

to the “Burden Reduction Rule”supported the idea that RCRA certifications should only be done 

by licensed professional engineers (See 71 FR 16868.) Upon further analysis and reflection, the 

Agency sees no reason to deviate from the position EPA held in the “Burden Reduction Rule.” 

Despite some concerns raised by commenters that problems could occur if an owner or operator 

hires an engineering firm that is small, inexperienced, or operating outside of their past 

professional practice, the Agency continues to believe that with the protections afforded by the 
Document submitted to conclude E.O.12866 Review

123

specific performance standards in this rule and the standards and ethics to which a qualified 

professional engineer is subject, situations in which an unqualified or un-licensed engineer 

certifies a technical demonstration will be avoided. Furthermore, it is important to reiterate that 

state licensing boards can investigate complaints of negligence or incompetence on the part of 

professional engineers, and may impose fines and other disciplinary actions, such as cease-anddesist orders or license revocation. (See 71 FR 16868.) In light of the third party oversight 

provided by the state licensing boards in combination with the numerous recordkeeping and 

recording requirements established in this rule, the Agency is confident that abuses of the 

certification requirements will be minimal and that human health and the environment will be 

protected.

The Agency wants to make it clear that qualified professional engineers can utilize a 

qualified team of professionals in performing the analyses that underlie these certifications. In 

most instances, EPA expects that the basis for certification by a qualified professional engineer 

will be the result of a team of professionals (e.g., geologists, hydrologists, scientists and 

engineers) who have collectively worked together in order to provide the data and analyses 

necessary for the professional engineer to certify the specific demonstration. 

The Agency is convinced that the change to the certification requirements to allow the 

use of in-house expertise will not compromise environmental safety. Professional engineers 

employed by a facility are more familiar with the facility’s particular situation and are in a 

position to provide more on-site review and oversight of the activity being certified. To this end, 

the Agency is also requiring that the qualified professional engineer be licensed in the state in 

which the CCR unit is located. The Agency has made this decision for a number of reasons, but 

primarily because state licensing boards can provide the necessary oversight on the actions of the 
Document submitted to conclude E.O.12866 Review

124

professional engineer and investigate complaints of negligence or incompetence as well as 

impose fines and other disciplinary actions such as cease-and-desist orders or license revocation. 

Oversight may not be as rigorous if the professional engineer is operating under a license issued 

from another state. 

Finally, the Agency disagrees with comments that professional geologists or geoscientists 

should be added to the list of those professionals that have expertise and authority to certify 

compliance with certain RCRA subtitle D regulatory requirements. In developing this final rule, 

the Agency has re-considered the qualifications necessary to certify compliance with the 

technical requirements of the rule and is limiting compliance certifications to qualified 

professional engineers only. While some environmental professionals, e.g., hydrologists, 

geologists may be qualified to make certain certifications, EPA is not convinced that 

hydrologists or geologists licensed by a state are held to the same standards as a professional 

engineer licensed by a state licensing board. For example, it is unclear that hydrologists or 

geologists are subject to the rigorous testing required by professional engineers or that state 

licensing boards can investigate complaints of negligence or incompetence. Further, professional 

engineers have licensing boards in all 50 states, a standard not achieved by other professional 

disciplines. Consequently, hydrologists, geologists, or other professionals may only perform 

analyses that underlie the certification, but it is the responsibility of a qualified professional 

engineer to make the actual certification. 

D. State and Public Notifications of Certifications 

To address concerns about the absence of adequate regulatory oversight under subtitle D, 

EPA proposed to require state and public notifications of the third party certifications, as well as 

other information documenting the decisions made or actions taken by the owner or operator to 
Document submitted to conclude E.O.12866 Review

125

comply with the technical criteria in the rule. As stated in the proposal and reiterated here, the 

Agency cannot conclude that the regulations promulgated in this rule will ensure there is no 

reasonable probability of adverse effects on health or the environment unless there is a 

mechanism for states and citizens, as the entities responsible for enforcing the rule, to effectively 

monitor or oversee its implementation. Mandated documentation and transparency of the owner 

or operator’s actions to comply with the rule provides this mechanism, and will help to minimize 

the potential for abuse. The proposal specified that the documentation of how the various 

technical standards had been met were to be placed in the facility’s operating record, along with 

notification to the appropriate state authority. Additionally, EPA proposed to require the owner 

or operator to maintain a website available to the public that would also provide access to this 

documentation. EPA proposed that owners or operators post notices and relevant information on 

the internet site with a link clearly identified as being a link to notifications, reports, and 

demonstrations required under the regulations. While EPA recognized that the internet is 

currently the most widely accessible means for gathering and disseminating information, the 

Agency also solicited comments regarding alternative methods to provide notifications to the 

public and the states. The Agency also solicited comment on whether to require the 

establishment of a publicly accessible internet site to provide regulatory information to the public 

and the states, including whether there could be homeland security implications associated with 

internet posting of information, and whether the posting would duplicate information that is 

already available to the public through the state. 

In response to most of these proposals, the Agency received little comment. Significant 

comment, however, was received on the publicly accessible internet site. Commenters argued 

that absent specific statutory authorization, it was inappropriate for EPA to delegate a regulatory 
Document submitted to conclude E.O.12866 Review

126

oversight function to the regulated community by requiring the creation of a website and 

posting of regulatory compliance information. Commenters identified at least three substantial 

problems associated with “outsourcing information management responsibilities” to CCR 

facilities. First, commenters argued that EPA lacked the authority to impose such a requirement. 

Specifically, the commenters alleged that no statute authorizes EPA to demand that private 

parties act as an information clearinghouse for information pertaining to EPA’s regulatory 

functions, either generally or in the specific context of CCR. To the contrary, the commenters 

argued, public information access statutes, such as the Freedom of Information Act are 

predicated on an assumption that information held by the government is presumptively public, 

while information held by a private entity presumptively is not.

Second, some commenters were concerned that facilities would not post information the 

facility deems to be confidential (e.g., the structural stability of ash pond impoundments) and by 

attempting to outsource the information management role to industry, EPA effectively allows 

industry to make the initial determination as to confidentiality and places the burden on citizens 

and EPA to take action to compel disclosure.

Third, commenters were concerned that citizen groups would not accept an electric 

utility’s self-reported information, regardless of the amount of effort the facility exerts to ensure 

the accuracy of the information, without a regulatory agency acting as the intermediary or 

providing some degree of oversight (e.g., EPA’s Toxic Release Inventory, EPA’s Biennial 

Report of hazardous waste facilities). By requiring citizen groups to obtain their information 

from industry instead of a regulator, the commenters argued that EPA is inviting conflict as to 

the adequacy of data and the sufficiency of the utilities’ responses to citizen groups’ requests for 

clarification or additional information. The fact that the industry has provided information to a 
Document submitted to conclude E.O.12866 Review

127

federal agency, subject to criminal penalties for providing false information, provides a useful 

public assurance of the integrity of the information.

Other commenters stated that the proposed requirement to maintain a website was

excessive, and generated a regulatory burden upon companies that serves no useful function. 

Commenters urged that the same purpose could be served simply through making the 

certification of the registered professional engineer available on the website. Other commenters 

argued that internet posting of information on a surface impoundment's construction raised 

homeland security issues. These commenters alleged that the information “can be extremely 

sensitive and may contain information that could be used by certain individuals with an intent to 

destroy a dam (e.g., engineering information on the structure's foundation, detailed information 

on physical and engineering properties, the basis for the structure hazard classification, slope 

stability information, etc.).”

Finally, some commenters offered an alternative to the requirement to establish and 

maintain a publicly accessible internet site. Under this alternative the information would be 

included in the owner or operator’s operating record only, and persons with “legitimate interests 

in reviewing these data” could make a written request to the owner or operator or the permitting 

authority to obtain the information. The commenters alleged that this would also allow the 

owner, operator, and federal and state authorities to know the names and identities of all 

organizations requesting information on the facility, which would help protect against the misuse 

of these data. 

EPA disagrees that RCRA section 4004(a) does not authorize EPA to require facilities to 

disclose all of the information required under these final rule provisions. Section 4004(a) 

delegates broad authority to EPA to establish criteria governing facilities’ management of solid 
Document submitted to conclude E.O.12866 Review

128

waste, requiring only that such criteria ensure that there will be no reasonable probability of 

adverse effects on health or the environment from the disposal of solid waste. The statute 

imposes no limits on the actions EPA may require facilities to perform to achieve that level of 

protection. Moreover, unlike other statutes, e.g., the Toxic Substances Control Act, or the 

Federal Insecticide, Rodenticide and Fungicide Act, RCRA contains neither provisions that grant 

facilities the right to withhold regulatory compliance information from the public, nor provisions 

that establish any reasonable expectation that such information will be kept confidential. To the 

contrary, section 7004 explicitly provides that [p]ublic participation in the ...implementation, 

and enforcement of any regulation under this chapter shall be provided for, encouraged, and 

assisted by the Administrator.” 42 U.S.C. § 6974(b). And in fact, this kind of information would 

routinely be publically available under the permitting process for hazardous waste facilities. 

Accordingly, RCRA provides more than ample authority to support these requirements. 

As repeatedly discussed throughout this preamble, under section 4004(a) EPA must be 

able to demonstrate, based on the record available at the time the rule is promulgated that the 

final rule provisions will achieve the statutory standard. EPA explained in the proposal that a key 

component of EPA’s support for determining that the rule achieves the statutory standard is the 

existence of a mechanism for states and citizens to monitor the situation, such as when 

groundwater monitoring shows evidence of potential contamination, so that they can determine 

when intervention is appropriate. The existence of effective oversight measures provides critical 

support for the statutory finding, particularly with respect to some of the more flexible 

alternatives EPA has adopted in certain of the technical standards in response to commenters’ 

requests for greater flexibility. These “transparency” requirements serve as a key component by 

ensuring that the entities primarily responsible for enforcing the requirements have access to the 
Document submitted to conclude E.O.12866 Review

129

information necessary to determine whether enforcement is warranted. Unlike a federal or state 

regulatory authority, private citizens cannot access a private facility to conduct inspections. 

While EPA encourages states to adopt and implement a CCR regulatory program, and seek 

EPA’s approval of it via a State Solid Waste Management Plan, EPA cannot require it. The final 

rule therefore must establish oversight mechanisms that will function effectively even in the 

absence of a state regulatory authority. 

Such notifications will also reduce the incentives for owners or operators to abuse the 

rule’s self-implementing requirements, and can improve compliance. Indeed, the public 

disclosure of information is an increasingly common and important regulatory tool, as evidenced 

by the 2010 guidance issued by the Office of Management and Budget (OMB), with principles to 

assist agencies in using information disclosure to achieve regulatory objectives.

Thus, even if the commenters were correct that there exists a general “presumption” that 

information held by private entities need not be made publically available, that presumption can 

be, and has been, effectively rebutted by the facts at hand.

None of the alternatives offered by the commenters would fulfill these same objectives. 

For example, simply making the certification of the qualified professional engineer available on 

the website without the underlying support information fails to provide the same incentives 

because no one could evaluate the accuracy of that certification. This alternative could also 

present the same concerns raised in comments on other sections of the rule, i.e., that such a 

requirement could place the engineer at great risk of being subject to lawsuits. Requiring persons 

with “legitimate interests in reviewing these data” to request the data from the owner/operator 

also fails to provide an effective guarantee, as facilities that have failed to comply will have a 

strong incentive to withhold information documenting their non-compliance, however 
Document submitted to conclude E.O.12866 Review

130

“legitimate” the request. And as noted, the absence of a guaranteed state permitting program 

means that requiring citizens to request information from such entities is also not a viable 

alternative. 

Given the absence of a guaranteed regulatory authority, EPA also disagrees that posting such 

information on a company internet site is necessarily duplicative, particularly in those states that 

have no regulatory program for controlling CCR. In addition, state requirements, whether 

pursuant to permits or other regulatory mechanisms, may not necessarily correspond to the 

requirements of this rule. 

EPA acknowledges that parties may be suspicious of information self-reported by 

regulated entities. However, it is important to remember that facilities that provide information in 

compliance with these regulation remain subject to the penalties for providing false information 

under 18 U.S.C. § 1001, even though the information will not be submitted to EPA. For example, 

the Tenth Circuit has held that federal jurisdiction lies under 18 U.S.C. § 1001 when a defendant 

has submitted false information to a state delegated to enforce a federal environmental statute. 

United States v. Wright, 988 F. 2d 1036 (10th Cir. 1993) (defendant submitted false monitoring 

reports required by the Safe Drinking Water Act to Oklahoma officials). This is consistent with 

rulings in other areas that the false statement need not be made directly to the federal 

government. United States v. Uni Oil Co., 646 F.2d 946, 954-55 (9th Cir. 1981); see also United 

States v. Patullo, 709 F.2d 1178, 1180 (7th Cir.1983); United States v. Ross, 77 F.3d 1525, 1544 

(7th Cir.1996) (“This court has repeatedly found the submission of a fraudulent statement to a 

private (or non-federal government) entity to be within the jurisdiction of a federal agency where 

the agency has given funding to the entity and fraudulent statements cause the entity to utilize the 
Document submitted to conclude E.O.12866 Review

131

funds improperly.”). As commenters recognized, the potential for criminal penalties under 18 

U.S.C. §1001 provides a significant guarantee, as well as a strong incentive for compliance. 

EPA also disagrees with the comments raising concern about the homeland security

implications of posting information on a CCR surface impoundment’s construction, as it relates 

to structural stability. Much of the information relevant to an impoundment’s structural stability 

is currently available through Google Earth or through EPA’s website. For example, EPA’s 

website currently provides access to all of the information from the responses to EPA’s original 

104(e) information requires and the information obtained through the CCR dam integrity 

assessments. This information can be accessed at the following pages: 

http://www.epa.gov/osw/nonhaz/industrial/special/fossil/surveys/index.htm, 

http://www.epa.gov/osw/nonhaz/industrial/special/fossil/surveys2/index.htm, and 

http://www.epa.gov/osw/nonhaz/industrial/special/fossil/ccrs-fs/index.htm. Moreover, the 

Department of Homeland Security has cleared both the internet posting of all of the information 

currently on EPA’s website, as well as, in general, information on the design, hydraulic 

parameters, volume of contained liquids and solids, and hazard rating of all major CCR surface 

impoundments across the U.S.

VI. Development of the Final Rule – Technical Requirements 

A. Applicability

EPA proposed general provisions to identify those solid waste disposal units subject to 

the proposed RCRA subpart D requirements (i.e., CCR landfills and CCR surface impoundments 

as defined under proposed § 257.40(b)). The applicability section also identified three of the 

existing subpart A criteria that would continue to apply to these facilities: § 257.3-1 Floodplains, 
Document submitted to conclude E.O.12866 Review

132

§ 257.3-2 Endangered Species, and § 257.3-3 Surface Water. Consistent with RCRA section 

4004(c), EPA specified an effective date of 180 days after publication of the final rule. 

The Agency received numerous comments on this part of the rule. In general, 

commenters were concerned with three specific areas. First, commenters requested additional 

clarification as to the specific sources of CCR that would be subject to the requirements of the 

rule, i.e., CCR generated by the electric utilities and independent power producers. Second, 

commenters requested clarification on the applicability of the proposed regulations to MSWLFs 

disposing of CCR and third, the definition and status of “uniquely associated wastes.” Uniquely 

associated wastes are addressed in Unit XIII of this preamble. EPA also received numerous 

comments regarding the proposal to apply the rule to “inactive” CCR surface impoundments that 

had not completed closure prior to the effective date of the rule. 

EPA is finalizing minimum national criteria that apply to owners and operators of new 

and existing CCR landfills and CCR surface impoundments, including any lateral expansions of 

these units that dispose, or otherwise conduct solid waste management of CCR generated from 

the combustion of coal at electric utilities and independent power producers. The rule applies 

only to CCR disposal units at “active” electric utilities and independent power producers, i.e., 

those that generate electricity, regardless of the fuel currently used to produce electricity. 

However, disposal units at facilities that are “closed”—i.e., the entire facility has been 

permanently taken out of service and no longer produces electricity—are outside of the scope of 

this rule. 

Unless otherwise provided, the rule applies to CCR disposal units located both on-site 

and off-site of the electric utility or independent power producer. 

1. CCR Generated by Non-Utility Boilers
Document submitted to conclude E.O.12866 Review

133

The requirements of this rule do not apply to wastes, including fly ash, bottom ash, boiler 

slag, and FGD materials generated at facilities that are not part of the electric power sector or an 

independent power producer and that use coal as the fuel in non-utility boilers, such as 

manufacturing facilities, universities, and hospitals. Industries that primarily burn coal to 

generate power for their own purposes (i.e., non-utilities), also known as combined heat and 

power (CHP) plants, are primarily engaged in business activities, such as agriculture, mining, 

manufacturing, transportation, and education. The electricity that they generate is mainly for 

their own use, but any excess may be sold in the wholesale market. According to the Energy 

Information Administration (EIA), CHPs produced less than one percent of the total electricity 

generated from coal combustion in 2013 and, similarly, burned less than one percent of the total 

coal consumed for electricity generation or less than 5 million tons 

(http://www.eia.gov/electricity/data.cfm). 

EPA never proposed to include these wastes in the rule because EPA lacked critical data 

from these facilities that would allow us to address key Bevill criteria (see 75 FR 35165). These 

other industries, and the manufacturing industries in particular, generate other types of wastes 

which are likely to be mixed or co-managed with the CCR at least at some facilities. As a result, 

the chemical compositions of the co-managed wastes are likely to be fundamentally different 

from the chemical composition of CCR generated by electric utilities or independent power 

producers. In addition, EPA noted that insufficient information was available on non-utility 

boilers burning coal to determine whether a regulatory flexibility analysis would be required 

under the Regulatory Flexibility Act, and to conduct one if it is necessary. Without such data, we 

were unable to fully assess CCR wastes from non-utility operations and indicated that we would 

decide on an appropriate course of action for these wastes after completing this rulemaking (see 
Document submitted to conclude E.O.12866 Review

134

75 FR 35129).

Several commenters stated that EPA’s decision to propose limiting the scope of the rule 

only to CCR generated by the electric power sector (electric utilities and independent power 

producers) was arbitrary. These commenters claimed that CCR generated by the electric power 

sector and CCR generated by non-utilities are generally comparable in physical and chemical 

composition and are typically managed similarly. As a result, these commenters suggested that 

EPA amend the applicability of the rule to subject all facilities that generate CCR to the same 

disposal requirements. EPA also received comments maintaining that important differences exist 

between CCR generated by electric power sector facilities and non-utility facilities, and that 

supported EPA’s proposed decision to exclude CCR generated by non-utilities from the rule. 

Differences identified by the commenters included waste management issues (e.g., mixing and 

subsequent co-management of non-utility CCR and other industrial wastes generated by nonutilities), CCR generation rates, CCR management unit design, and CCR management unit 

operation. In response to our request for additional information, a few commenters provided 

either waste characterization data for non-utility CCR or information on alleged damage cases 

involving non-utility CCR.

Based on the proposed rule, EPA cannot include these facilities in this final rule, even if 

the Agency had concluded that it had received the necessary information from commenters. 

EPA specifically stated its intention to exclude them, and clearly stated that it had not assessed 

the operations. (See 75 FR 35166.) The Agency provided no indication of any intention to 

include such facilities, and did not solicit comment on such an option. Moreover, under the 

Administrative Procedure Act, the public must be given the opportunity to comment on not only 

the information that would support such an action, but also EPA’s evaluation of that information, 
Document submitted to conclude E.O.12866 Review

135

and the reasoning behind the Agency’s decision. And with respect to this subset of facilities, no 

such opportunity has been presented. EPA will consider the information provided by 

commenters at a future point, and will determine whether the information is sufficient to address 

key Bevill criteria and to decide on the appropriate regulatory scheme for disposal of CCR

generated by non-utilities. Accordingly, this rule does not apply to owners and operators of 

landfills and surface impoundments in which CCR are disposed that were generated by nonutility boilers burning coal.

2. CCR Generated Primarily from the Combustion of Fuels Other than Coal

These requirements also do not apply to fly ash, bottom ash, boiler slag, and flue gas 

desulfurization materials, generated primarily from the combustion of fuels (including other 

fossil fuels) other than coal, for the purpose of generating electricity unless the coal comprises 

more than fifty percent (50%) of the fuel burned on a total heat input or mass input basis, 

whichever results in the greater mass feed rate of coal (see § 266.112). Fuel mixtures that contain 

less than 50% coal are not considered to be CCR, but other fossil fuel wastes. Other fossil fuels 

that are typically co-combusted with coal are oil and natural gas. In the May 22, 2000 Regulatory 

Determination, EPA determined that it is not appropriate to establish national regulations 

applicable to oil combustion wastes (OCW) because: (1) we found in most cases that OCW, 

whether managed alone or co-managed, are rarely characteristically hazardous; (2) we have not 

identified any beneficial uses that are likely to present significant risks to human health or the 

environment; (3) we identified no significant ecological risks posed by land disposal of OCW; 

(4) we identified only one documented damage case involving OCW in combination with coal 

combustion wastes, and it did not affect human receptors; and (5) except for two unlined surface 

impoundments, we have not identified any significant risks to human health and the environment 
Document submitted to conclude E.O.12866 Review

136

associated with any waste management practices. Similarly, EPA determined that regulating 

natural gas combustion wastes is not warranted because the burning of natural gas produces 

virtually no solid waste. Therefore, the Agency has determined that regulations for wastes

generated primarily from the combustion of fuels (including other fossil fuels) other than coal are 

not warranted unless the fuel mixture consists primarily of coal.

3. Placement of CCR in Minefilling Operations

Consistent with the approach in the proposed rule, this rule does not apply to CCR placed 

in active or abandoned underground or surface coal mines. The U. S. Department of Interior 

(DOI) and EPA will address the management of CCR in minefills in a separate regulatory 

action(s). EPA will work with the OSM to develop effective federal regulations to ensure that 

the placement of coal combustion residuals in minefill operations is adequately controlled. In 

doing so, EPA and OSM will consider the recommendations of the National Research Council 

(NRC), which, at the direction of Congress, studied the health, safety, and environmental risks 

associated with the placement of CCR in active and abandoned coal mines in all major U.S. coal 

basins. The NRC published its findings on March 1, 2006, in a report entitled ‘‘Managing Coal 

Combustion Residues (CCR) in Mines,’’ which is available at 

http://books.nap.edu/openbook.php?isbn=0309100496.

The report concluded that the ‘‘placement of CCR in mines as part of coal mine 

reclamation may be an appropriate option for the disposal of this material. In such situations, 

however, an integrated process of CCR characterization, site characterization, management and 

engineering design of placement activities, and design and implementation of monitoring is 

required to reduce the risk of contamination moving from the mine site to the ambient 

environment.’’ The NRC report recommended that enforceable federal standards be established 
Document submitted to conclude E.O.12866 Review

137

for the disposal of CCR in minefills to ensure that states have specific authority and that states 

implement adequate safeguards. The NRC Committee on Mine Placement of Coal Combustion 

Wastes also stated that OSM and its SMCRA state partners should take the lead in developing 

new national standards for CCR use in mines because the framework is in place to deal with 

mine-related issues. Consistent with the recommendations of the National Academy of Sciences, 

EPA anticipates that the U.S. Department of the Interior (DOI) will take the lead in developing 

these regulations. EPA will work closely with DOI throughout that process. 

4. Municipal Solid Waste Landfills

The issue receiving the majority of comment in this section focused on the applicability 

of the rule to MSWLFs accepting CCR. The vast majority of commenters on this issue requested 

that EPA clarify that permitted MSWLFs, receiving CCR as daily cover or for disposal were not 

covered by the rule. 

While most CCR is currently disposed of at electric utility owned CCR landfills or 

surface impoundments, there is no prohibition against disposing of CCR in state-permitted 

MSWLFs. However, many commenters interpreted the proposed CCR subtitle D regulations to 

apply to a state permitted MSWLF disposing of CCR, which as a consequence would be subject 

to the additional burden of posting documentation to a website, having a professional engineer 

review certification, etc. (See 75 FR 35210, where the preamble states that under a subtitle D 

regulation, regulated CCR wastes shipped off-site for disposal would have to be sent to facilities 

that meet the standards above.) Commenters argued that since MSWLFs were never mentioned 

in the proposed rule, that it should be made clear that the rule did not apply to these facilities. 

Commenters further contended that since the requirements for CCR landfills were directly 

modeled from the MSWLF requirements found at 40 CFR 258, disposal in MSWLFs would be 
Document submitted to conclude E.O.12866 Review

138

protective of human health and the environment. Commenters also contended that a benefit of 

MSWLFs would be their ability to provide additional capacity for the disposal of CCR as 

utilities seek to close, upgrade, or develop their own compliant CCR disposal sites. 

EPA recognizes that there are MSWLFs that either accept CCR for disposal, use CCR for 

as daily cover, or both. Since the proposed and final RCRA subtitle D standards for CCR 

landfills are modeled after the standards for MSWLFs found at 40 CFR 258, EPA has concluded 

that disposal of CCR in MSW landfills is as protective as disposal in a CCR landfill and that 

permitted MSWLFs are not subject to the requirements of this rule. Like the MSWLF 

requirements, the CCR technical criteria require new units to have composite liners or their 

equivalent, and all units are subject to location restrictions, run-on and run-off controls, fugitive 

dust controls, groundwater monitoring and corrective action, closure and post-closure care 

requirements.38

While the MSWLF fugitive dust criteria (air criteria) are not as specific as those in this 

rule, § 258.4(a) states that “owners or operators of all MSWLFs must ensure that the units not 

violate any applicable requirements developed under a State Implementation Plan (SIP) 

approved or promulgated by the Administrator pursuant to section 110 of the Clean Air Act, as 

amended. It is expected that states will impose additional requirements to address fugitive dusts, 

of the sort codified in Illinois’ 415 ILCS 5/9(a)(2012)39 and enforced by the state (see People of 

 

38 One significant difference however is that MSWLFs are required to have financial assurance, a 

requirement not applicable to CCR under the subtitle D requirements.

39 “No person shall (a) Cause or threaten or allow the discharge or emission of any contaminant into the 

environment in any state so as to cause or tend to cause air pollution in Illinois, either alone or in 

combination with contaminants from other sources, or so as to violate regulations or standards adopted by 

the Board under this Act; (b) Construct, install or operate any equipment, facility, vehicle, vessel, or 

aircraft capable of causing or contributing to air pollution or designed to prevent air pollution, of any 

typed designated by Board regulations, (1) without a permit granted by the Agency unless otherwise 

exempt by this Act or Board regulations; or (2) in violation of any conditions imposed by such permit.”
Document submitted to conclude E.O.12866 Review

139

the State of Illinois v KCBX Terminals Company, Injunction no. 2013CH24788 in the Circuit 

Court of Cook County, Illinois. Moreover, if used as a daily cover, § 258.21 requires that the 

alternative cover (i.e., CCR) control disease, vectors, odors, blowing litter, and scavenging 

without presenting a threat to human health and the environment. 

The Agency is not requiring MSWLFs that receive CCR for disposal or for use as daily 

cover to modify their groundwater monitoring programs to comply with the rule; however the 

Agency expects that State Directors will require MSWLFs to modify their MSWLF permits to 

address the addition of CCR to the unit as it relates to groundwater monitoring and corrective

action. Section 258.54(a)(2) allows for the Director of an approved state to establish an 

alternative list of inorganic indicator parameters for a MSWLF unit if the alternative parameters 

provide a reliable indication of inorganic releases from the MSWLF unit to the groundwater (i.e., 

as would be the case if CCR was disposed in the MSWLF unit). In determining alternative 

parameters, the Director shall consider, among other things: (1) the types, quantities, and 

concentrations in wastes managed at the MSWLF unit; (2) the mobility, stability, and persistence 

of waste constituents or their reaction products in the unsaturated zone beneath the MSWLF unit; 

and (3) the detectability of indicator parameters, waste constituents, and reaction products in the 

groundwater. In situations where the MSWLF unit is receiving CCR for disposal and/or daily 

cover, EPA expects the controlled management of CCR in these units. Specifically, EPA expects 

State Directors to utilize the provisions in § 258.54(a)(2) to revise the detection monitoring 

constituents to include those constituents being promulgated in this rule under § 257.90. These 

detection monitoring constituents or inorganic indicator parameters are: boron, calcium, chloride, 

fluoride, pH, sulfate and total dissolved solids (TDS). These inorganic indicator parameters are 

known to be leading indicators of releases of contaminants associated with CCR and the Agency 
Document submitted to conclude E.O.12866 Review

140

strongly recommends that State Directors add these constituents to the list of indicator 

parameters to be monitored during detection monitoring of groundwater if and when a MSWLF 

decides to accept CCR. 

The Agency has concluded that CCR can readily be handled in permitted MSWLFs 

provided that they are evaluated for waste compatibility and placement as required under the Part 

258 requirements. Furthermore, consistent with the recordkeeping requirements in § 258.29, the 

Agency further expects State Directors to encourage MSWLF units receiving CCR after the 

effective date of this rule to do so pursuant to a “CCR acceptance plan” that is maintained in the 

facility operating record. This plan would assure that the MSWLF facility is aware of the 

physical and chemical characteristics of the waste received (i.e., CCR) and handles it with the 

additional precautions necessary to avoid dust, maintain structural integrity, and avoid 

compromising the gas and leachate collection systems of the landfill so that human health and 

the environment are protected. While the Agency sees no need to impose duplicative 

requirements for MSWLFs that receive CCR for disposal or daily cover; development of these 

acceptance plans as well as a revised list of groundwater detection monitoring constituents will 

help ensure that CCR is being managed in the most protective manner consistent with the Part 

258 requirements.

5. Inactive CCR Surface Impoundments

The final rule also applies to “inactive” CCR surface impoundments at any active electric 

utilities or independent power producers, regardless of the fuel currently being used to produce 

electricity; i.e., surface impoundments at any active electric utility or independent power 

producer that have ceased receiving CCR or otherwise actively managing CCR. While it is true 

that EPA exempted inactive units from the part 258 requirements in 1990, the original subtitle D 
Document submitted to conclude E.O.12866 Review

141

regulations at 40 CFR part 257 (which are currently applicable to CCR wastes) applied to “all 

solid waste disposal facilities and practices” except for eleven specifically enumerated 

exemptions (none of which are relevant). 40 CFR 257.1(c). See also, 40 CFR 257.1(a)(1)-(2). 

And as discussed in greater detail below, subtitle D of RCRA does not limit EPA’s authority to 

active units—that is, units that receive or otherwise manage wastes after the effective date of the 

regulations. EPA has documented several damage cases that have occurred due to inactive CCR 

surface impoundments, including the release of CCR and wastewater from an inactive CCR 

surface impoundment into the Dan River which occurred since publication of the CCR proposed 

rule. As discussed in the proposal, the risks associated with inactive CCR surface impoundments 

do not differ significantly from the risks associated with active CCR surface impoundments; 

much of the risk from these units is driven by the hydraulic head imposed by impounded units. 

These conditions remain present in both active and inactive units, which continue to impound 

water along with CCR. For all these reasons, the Agency has concluded that inactive CCR 

surface impoundments require regulatory oversight. 

The sole exception is for “inactive” CCR surface impoundments” that have completed 

dewatering and capping operations (in accordance with the capping requirements finalized in this 

rule) within three years of the effective date. EPA considers these units to be analogous to 

inactive CCR landfills, which are not subject to the final rule. As noted, EPA’s risk assessment 

shows that the highest risks are associated with CCR surface impoundments due to the hydraulic 

head imposed by impounded water. Dewatered CCR surface impoundments will no longer be 

subjected to hydraulic head so the risk of releases, including the risk that the unit will leach into 

the groundwater, would be no greater than those from CCR landfills. Similarly, the requirements 

of this rule do not apply to inactive CCR landfills—which are CCR landfills that do not accept 
Document submitted to conclude E.O.12866 Review

142

waste after the effective date of the regulations. The Agency is not aware of any damage cases 

associated with inactive CCR landfills, and as noted, the risks of release from such units are 

significantly lower than CCR surface impoundments or active CCR landfills. In the absence of 

this type of evidence, and consistent with the proposal, the Agency has decided not to cover 

these units in this final rule. 

Under both the subtitle C and subtitle D options, EPA proposed to regulate “inactive” 

CCR surface impoundments that had not completed closure prior to the effective date of the rule. 

EPA proposed that if any inactive CCR surface impoundment had not met the interim status 

closure requirements (i.e., dewatered and capped) by the effective date of the rule, the unit would 

be subject to all of the requirements applicable to CCR surface impoundments. Under the 

subtitle C option, those requirements would have included compliance with the interim status 

and permitting regulations. Under subtitle D, such units would have been required to comply 

with all of the criteria applicable to CCR surface impoundments that continued to receive wastes, 

including groundwater monitoring, corrective action, and closure. 

EPA acknowledged that this represented a departure from the Agency’s long-standing 

implementation of the regulatory program under subtitle C. While the statutory definition of 

“disposal” has been broadly interpreted to include passive leaking, historically EPA has 

construed the definition of “disposal” more narrowly for the purposes of implementing the 

subtitle C regulatory requirements. For examples see 43 FR 58984 (Dec. 18, 1978); and 45 FR 

33074 (May 1980). Although in some situations, post-placement management has been 

considered to be disposal triggering RCRA subtitle C regulatory requirements, e.g., dredging of 

impoundments or management of leachate, EPA has generally interpreted the statute to require a 

permit only if a facility treats, stores, or actively disposes of the waste after the effective date of 
Document submitted to conclude E.O.12866 Review

143

its designation as a hazardous waste. EPA explained that relying on a broader interpretation was 

appropriate in this instance given that the substantial risks associated with currently operating 

CCR surface impoundments, i.e., the potential for leachate and other releases to contaminate 

groundwater and the potential for catastrophic releases from structural failures, were not 

measurably different than the risks associated with “inactive” CCR surface impoundments that 

continued to impound water, even though the facility had ceased to place additional wastes in the 

unit. EPA noted as well that the risks are primarily driven by the older existing units, which are 

generally unlined.

In the section of the preamble discussing the subtitle D option, EPA did not expressly 

highlight the application of the rule to inactive CCR surface impoundments, but generally 

explained that EPA’s approach to developing the proposed subtitle D requirements for surface 

impoundments (which are not addressed by the part 258 regulations that served as the model for 

the proposed landfill requirements) was to seek to be consistent with the technical requirements 

developed under the subtitle C option. (See 75 FR 35193.) (“In addition, EPA considered that 

many of the technical requirements that EPA developed to specifically address the risks from the 

disposal of CCR as part of the subtitle C alternative would be equally justified under a RCRA 

subtitle D regime...The factual record—i.e., the risk analysis and the damage cases—supporting 

such requirements is the same, irrespective of the statutory authority under which the Agency is 

operating...Thus several of the provisions EPA is proposing under RCRA subtitle D either 

correspond to the provisions EPA is proposing to establish for RCRA subtitle C requirement. 

These provisions include the following regulatory provisions specific to CCR that EPA is 

proposing to establish: Scope and applicability (i.e., who will be subject to the rule 

criteria/requirements) ...”)(emphasis added). 
Document submitted to conclude E.O.12866 Review

144

EPA received numerous comments on this aspect of the proposal. On the whole, the 

comments were focused on EPA’s legal authority under subtitle C to regulate inactive and closed 

units, as well as inactive and closed facilities. One group of commenters, however, specifically 

criticized the proposed subtitle D regulation on the ground that it failed to address the risks from 

inactive CCR surface impoundments. The majority of commenters, however, argued that RCRA 

does not authorize EPA to regulate inactive or closed surface impoundments. These commenters 

focused on two primary arguments: first, that RCRA’s definition of “disposal” cannot be 

interpreted to include “passive migration” based on the plain language of the statute, and second, 

that such an interpretation conflicted with court decisions in several circuits, holding that under 

CERCLA “disposal” does not include passive leaking or the migration of contaminants. 

In support of their first argument, commenters argued that the plain language of RCRA 

demonstrates that the requirements are “prospective in nature” and thus cannot be interpreted to 

apply to past activities, i.e., the past disposals in inactive CCR units. They also argued that the 

absence of the word “leaching” from the definition of “disposal” clearly indicates that Congress 

did not intend to cover passive leaking or migration from CCR disposal units. The commenters 

also selectively quoted portions of past EPA statements, claiming that these demonstrated that 

EPA had conclusively interpreted RCRA to preclude jurisdiction over inactive units and 

facilities. In particular, they pointed to EPA’s decision in 1980 not to require permits for closed 

or inactive facilities. 

Commenters cited several cases to support their second claim. These include, Carson 

Harbor Vill. v. Unocal Corp., 270 F.3d 863 (9th Cir. 2001); United States v. 150 Acres of Land, 

204 F.3d 698, 706 (2000); ABB Industrial Systems v. Prime Technology, 120 F.3d 351, 358 (2d 

Cir. 1997); United States v. CMDG Realty Co., 96 F.3d 706, 711 (3rd Cir. 1996); Joslyn Mfg. 
Document submitted to conclude E.O.12866 Review

145

Co. v. Koppers Co., 40 F.3d 750, 762 (5th Cir. 1994); Delaney v. Town of Carmel, 55 F. Supp. 

2d 237, 256 (S.D.N.Y. 1999); see also Interfaith Cmty. Org. v. Honey-Well Intl Inc., 263 F. 

Supp. 2d 796, 846 n.10 (D.N.J. 2003). The commenters acknowledge that these cases were all 

decided under CERCLA, but claim that the cases are all equally dispositive with respect to 

RCRA’s definition of disposal because CERCLA specifically incorporates by reference RCRA‘s 

statutory definition of disposal.

As an initial matter, it is important to correct certain misunderstandings contained 

throughout a number of the comments. First, EPA did propose to include inactive units under the 

subtitle D alternative. EPA clearly signaled its intent to cover the same universe of units and 

facilities covered under the subtitle C proposal. EPA did not include a corresponding discussion 

in its explanation of the subtitle D alternative because application of the criteria to inactive units 

did not represent such a significant departure from EPA’s past practice or interpretation. As 

discussed in more detail below, the original subtitle D regulations applied to all existing disposal 

units. See 40 CFR § 257.1(a)(1)-(2), (c) and 43 FR 4942-4943, 4944. 

Second, several commenters criticized EPA’s purported proposal to cover both “closed” 

and “inactive” surface impoundments, using the terms interchangeably. These same commenters 

also refer to both “inactive facilities” and “inactive units.” These are all different concepts, and 

EPA clearly distinguished between them. 

EPA proposed to regulate on “inactive” surface impoundments that had not completed 

closure of the surface impoundment before the effective date. “Inactive” surface impoundments 

are those that contain both CCR and water, but no longer receive additional wastes. By contrast, 

a “closed” surface impoundment would no longer contain water, although it may continue to 

contain CCR (or other wastes), and would be capped or otherwise maintained. There is little 
Document submitted to conclude E.O.12866 Review

146

difference between the potential risks of an active and inactive surface impoundment; both can 

leak into groundwater, and both are subject to structural failures that release the wastes into the 

environment, including catastrophic failures leading to massive releases that threaten both human 

health and the environment. This is clearly demonstrated by the recent spill in the Dan River in 

North Carolina, which occurred as the result of a structural failure at an inactive surface 

impoundment. Similarly, as demonstrated by the discovery of additional damage cases upon the 

recent installation of groundwater monitoring systems at existing CCR surface impoundments in 

Michigan and Illinois, many existing CCR surface impoundments are currently leaking, albeit 

currently undetected. These are the risks the disposal rule specifically seeks to address, and 

there is no logical basis for distinguishing between units that present the same risks. 

EPA did not propose to require “closed” surface impoundments to “reclose.” Nor did 

EPA intend, as the same commenters claim, that “literally hundreds of previously 

closed...surface impoundments - many of which were properly closed decades ago under state 

solid waste programs, have changed owners, and now have structures built on top of them -

would be considered active CCR disposal units.” Accordingly, the final rule does not impose any 

requirements on any CCR surface impoundments that have in fact “closed” before the rule’s 

effective date—i.e., those that no longer contain water and can no longer impound water. 

Further, EPA never proposed that the rule would apply to inactive facilities. The 

proposal was clear that the regulations would apply to active facilities—i.e., those that continue 

to generate electricity for distribution to the public, and those that continue to manage CCR. 

Consistent with that proposal, the final rule applies only to inactive surface impoundments at 

active electric utilities, i.e., facilities that are actively generating electricity irrespective of the 

fuel used. 
Document submitted to conclude E.O.12866 Review

147

Finally, some comments focused on issues that were specific to the plain language of 

subtitle C provisions. While most of the issues the commenters raised relate equally to EPA’s 

authority under both subtitles C and D, because the final rule establishes standards under subtitle 

D of RCRA, EPA has not addressed comments that are purely relevant or applicable to the extent 

of EPA’s authority under subtitle C. 

a. Plain Language of RCRA and EPA’s Past Interpretations

Under both subtitle C and subtitle D, EPA’s authority to regulate “inactive” units 

primarily stems from the agency’s authority to regulate “disposal.” The term is defined once in 

RCRA and applies to both subtitles C and D. Moreover, the definition explicitly includes 

“leaking” and “placing of any solid waste...into or on any land so that such [waste] or any 

constituent thereof may enter the environment...or be discharged into any waters, including 

ground waters.” 42 U.S.C. § 6903(3). 

Commenters focused on the past statements that EPA cited in the proposal in 

acknowledging that the Agency was proposing to revise its interpretation for this rulemaking. In 

general, the comments misconstrue the significance of these past statements. The cited passages 

merely explain that the permitting requirements in subtitle C were written to be “prospective in 

nature” and as a consequence, EPA has chosen to interpret “disposal” more narrowly in that 

context. Thus EPA’s historic interpretation under subtitle C was not based on an interpretation 

that the plain language of RCRA’s definition of “disposal” precluded reaching inactive units, but 

on a determination that a narrower interpretation would be reasonable in light of specific 
Document submitted to conclude E.O.12866 Review

148

language in sections 3004 and 3005, and the practical consequences of applying these

requirements to inactive facilities.40

None of EPA’s past statements included any interpretation that “leaking” does not 

include leaking from an inactive disposal unit, or that the statutory definition of “disposal” 

cannot be interpreted to apply to the current consequences of past disposals. To the contrary, 

EPA was clear in the original 1978 proposed hazardous waste regulations that leaking from 

inactive disposal units constitutes “disposal” under RCRA. 

Neither RCRA nor its legislative history discusses whether section 3004 standards for 

owners and operators of hazardous waste treatment, storage, or disposal facilities apply or were 

intended to apply to inactive facilities, i.e., those facilities which have ceased receiving, treating, 

storing, and disposing of wastes prior to the effective date of the subtitle C regulations. This is 

an important issue, however, because some, and perhaps most, inactive facilities may still be 

“disposing of waste within the meaning of that term in Section 1004(3) of RCRA. ‘Disposal’ 

includes:

the discharge, dumping, spilling, leaking,...of any solid waste or hazardous waste into or 

on any land or water so that such solid waste or hazardous waste or any constituent 

thereof may enter the environment or be emitted into the air or discharged into any 

waters, including ground waters.

Many inactive facilities may well be leaking solid or hazardous waste into groundwater 

and thus be “disposing” under RCRA. 

43 FR 58984 (emphasis added). 

 

40 It is also clear that certain subtitle C requirements in fact do apply to inactive units, for example, section 

3004(u) requires facilities to clean up releases from inactive units located on the facility site. 
Document submitted to conclude E.O.12866 Review

149

Note as well that EPA declined to impose requirements on “inactive facilities” not 

“inactive units at active facilities,” which are the entities covered in this final CCR rule. Further, 

the complications discussed in 1978 were specific to inactive or closed facilities: the concern 

that the present owner of the land on which an inactive site was located might have no 

connection (other than present ownership of the land) with the prior disposal activities. Id. 

These considerations are not relevant to inactive CCR surface impoundments at active electric 

utilities. 

EPA further clarified this position in the 1980 final hazardous waste rule, explaining that, 

while the Agency did not generally intend to regulate those portions of facilities that had closed 

before the effective date, there were exceptions to this, and that in individual cases, inactive 

portions of a facility—or in other words, inactive units, might be regulated. 

[O]wners and operators which continue to operate after the effective date of the 

regulations must ensure that portions of facilities closed before the effective date of these 

rules do not interfere with the monitoring or control of active portions. This requirement 

regulates the facility which operates under the RCRA regulations, although it may require 

the owner or operator before he receives a permit, or, as a permit condition, to take certain 

measures on portions of his facility closed before the effective date of these regulations. 

45 FR 33068. (See also 45 FR 33170.) In other words, EPA was clear that its jurisdiction under 

RCRA extended to these portions of the facility but that the Agency had made a policy choice 

not to exert its regulatory jurisdiction as a general matter over inactive facilities, choosing 

instead to rely on section 7003 and CERCLA to address the risks and require clean-up of these 

sites. EPA has adopted a substantially similar approach here, requiring the current owner or 

operator of an active facility to address the risks associated with an inactive portion of the facility 
Document submitted to conclude E.O.12866 Review

150

that could potentially interfere with the monitoring or control of the actively operating portion of 

the facility through leaking contaminants or other releases. 

Similarly, in the 1980 final rules, EPA expressly declined to revise the regulatory 

definition of disposal to exclude accidental or unintentional releases. EPA noted that 

“[r]egardless of whether a discharge of hazardous waste is intentional or not, the human health 

and environmental effects are the same. Thus intentional and unintentional discharges are 

included in the definition of “disposal.” (See 45 FR 33068.) While EPA revised other provisions 

to clarify that a permit would not be required for accidental discharges, EPA was clear that such 

activities are properly considered to be “disposal.” 

By contrast, EPA’s past implementation of subtitle D, following from the legislative 

history and the statutory language, consistently applied regulatory requirements equally to all 

facilities, without distinguishing between active and inactive or new and existing facilities. 

Congress was clear that subtitle D was intended to specifically address the problem of 

abandoned leaking “open dumps” scattered across the country, “where frequently the use of the 

site for waste disposal is neither authorized nor supervised.” H. Rep. No. 94-1491, p 37, 94th

Cong., 2d Sess (1976). For example, the report described the consequences when “the City of 

Texarcana Arkansas/Texas, abandoned its six open dumps, in 1968” to support the need to 

require open dumps to upgrade or close. Similarly, in describing the need for the legislation, the 

House report stated:

Disposal of solid wastes, including hazardous wastes, can have adverse 

environmental impacts in several ways. The following paragraphs discuss five different 

types of such impacts.
Document submitted to conclude E.O.12866 Review

151

(i) Perhaps the most pernicious effect is the contamination of groundwater by 

leachate from land disposal of waste. About half of the U.S. domestic water supply is from 

underground water, and thus is potentially subject to contamination. Such contamination 

is particularly vexing because often it is discovered after the damage is done and because 

the contamination is very long lasting. Thus leachate from a landfill or dump may not 

show up for years, maybe not even until after the landfill is closed.

Id at 89 (emphasis added). 

Consequently, subtitle D of RCRA provides clear authority to address inactive or 

abandoned disposal sites. The relevant provisions of RCRA subtitle D do not distinguish 

between “active” and “inactive” disposal units. Nor do any of the relevant provisions tie 

jurisdiction to the receipt or disposal of waste after a specific date. 

RCRA section 1004(14) defines an “open dump” as “any facility or site where solid 

waste is disposed of which is not a sanitary landfill which meets the criteria promulgated under 

section [4004] of this chapter and which is not a facility for disposal of hazardous waste.“ 42 

U.S.C. § 6903(14)(emphasis added). Section 4004(a) delegates broad authority to EPA to 

determine the facilities that will be considered “open dumps,” without any requirement that the 

units or facilities be in operation. “[T]he Administrator shall promulgate regulations containing 

criteria for determining which facilities shall be classified as sanitary landfills and which shall be 

classified open dumps within the meaning of this chapter.” 42 U.S.C. § 6944(a). Section 

4005(a), which is titled, “Closing or upgrading of existing open dumps,” is also not limited in 

scope: “Upon promulgation of criteria under [1008(a)(3)] of this title, any solid waste 

management practice of disposal of solid waste or hazardous waste which constitutes the open 

dumping of solid or hazardous waste is prohibited,...” 42 U.S.C. § 6945(a)(emphasis added). 
Document submitted to conclude E.O.12866 Review

152

See also, section 4003(a)(3), requiring state plans to provide for the closing or upgrading of “all 

existing open dumps”). 42 U.S.C. § 6943(a)(3)(emphasis added). 

Consistent with the statutory provisions, EPA’s current subtitle D regulations at 40 CFR 

257 apply to “all solid waste disposal facilities and practices” whether active or inactive, and did 

not differentiate between new and existing facilities.41 40 CFR § 257.1(c). See also, 40 CFR §

257.1(a)(1)-(2). EPA was clear in both the proposed and final rules that the rules applied to all 

existing facilities:

These criteria for the classification of disposal facilities apply to all “solid waste” and 

“disposal” facilities, which are defined in the Act [in](section 1004). 

43 FR 4942-4943, 4944. The final rule was equally clear: 

These criteria apply to the full range of facilities and practices for “disposal” of “solid 

waste,” as those terms are defined in the Act. 

44 FR 53440. (See also 44 FR 53438.) The final rule describes eight categories of materials or 

activities that are excluded; inactive facilities or units are not among them. This stands in stark 

contrast to the hazardous waste regulations, which, as discussed, specifically exempted inactive 

facilities from the permitting and associated regulatory requirements. 

b. Case Law on the Definition of Disposal

EPA also disagrees with the commenters’ second claim that regulating inactive surface 

impoundments would be inconsistent with case law in six circuits. The commenters are correct 

that some courts have held that the subsequent passive migration of contamination left on-site is 

insufficient to support liability against a third party that merely owned the property under 

 

41The regulations establish eleven specifically enumerated exemptions, none of which are relevant to the 

units at issue.
Document submitted to conclude E.O.12866 Review

153

CERCLA. But the commenters misconstrue this case law and fundamentally overstate its 

significance to the issue at hand. Of greater significance, however, is that federal courts have 

almost universally reached different conclusions under RCRA, holding that the statutory 

definition of disposal does include the passive migration of contamination from previously 

disposed of wastes. 

As an initial matter, the issue decided by the courts in the cited CERCLA cases was 

narrower than the commenters allege; these cases generally focused on whether current or past 

owners of land contaminated by the activities of other owners were liable for passive migration 

that occurred during their ownership of the land. This is very different than the situation at hand, 

in which regulatory requirements are being imposed to address the existing and future 

contamination caused by the past and current activities of the current owner. 

In addition, these decisions were largely predicated on language that is unique to 

CERCLA, rather than on a definitive reading of RCRA’s definition of disposal. See, e.g., United 

States v. CMDG Realty Co., supra at 712-717. For example, in CMDG Realty, the court found 

that passive migration was not disposal because Congress had clearly distinguished between 

“releases,” and “disposal,” defining the two terms differently and imposing liability on different 

parties for the two activities. Id. Accord, Carson Harbor Village, supra, at 880-885; ABB 

Industrial Systems v. Prime Technology, supra at 358. 

Moreover, even under CERCLA courts have not universally reached the same 

conclusions on whether “passive migration” can be considered “disposal.” See, e.g., Nurad, Inc. 

v. William E. Hooper & Sons Co., 966 F.2d 837, 844-46 (4th Cir. 1992)(concluding that because 

the definition of disposal includes "leaking," prior owners are liable if they acquired a site with 

leaking barrels or underground storage tanks even though the prior owner's actions are purely 
Document submitted to conclude E.O.12866 Review

154

passive); ABB Industrial Systems, Id., n.3 (expressly declining to decide whether passive 

migration could ever be considered “disposal”). 

But in any event, courts have consistently interpreted RCRA to apply to passive 

migration. Two cases under RCRA are the most directly analogous to the current situation as 

they address the extent of EPA’s authority to regulate based on the statutory definition of 

“disposal”: In re Consolidated Land Disposal Regulation Litigation, 938 F.2d 1386 (D.C. Cir. 

1991), and United States v. Power Engineering Co., 10 F. Supp. 2d 1145 (D. Colo. 1998), aff'd

191 F.3d 1224 (10th Cir. 1999). In both cases, the court considered whether EPA could impose 

or enforce regulatory requirements to address passive migration under the interpretation that this 

constituted “disposal” under RCRA. And in both cases the court agreed that RCRA’s definition 

encompassed such activities. 

The issue in Consolidated Land Disposal was whether EPA could require closed 

hazardous waste facilities to obtain a “post-closure” permit. 938 F.2d at 1388-1389. EPA had 

relied on the definition of disposal to support the regulation, concluding that a facility "at which 

hazardous wastes have been disposed by placement in or on the land" remains subject to both 

permitting and regulation because "such hazardous wastes or constituents may continue 'leaking' 

or 'may enter the environment or be emitted . . . or discharged . . .' " into the environment.” Id. 

Similar to the commenters’ current arguments, the petitioners argued that under § 3005, a permit 

can only be required for “on-going activities” - the treatment, storage, or disposal of waste at 

such facilities - not for the facility itself post-closure. The petitioners argued that linguistically, 

“disposal . . . is not a continuing activity but occurs anew each time waste is placed into or on 

land." The DC Circuit summarily rejected the petitioners’ interpretation, holding that this “may 

be one way in which the word is used in ordinary language, but is not necessarily how it is used 
Document submitted to conclude E.O.12866 Review

155

in the statute; the equation of "disposal" with "leaking," which is a continuous phenomenon 

rather than a discrete event, is enough to blunt the sting of the petitioners' point.” Id. This case 

is essentially dispositive of the issue, given the similarities between the requirement for a postclosure permit and the final requirements applicable to inactive CCR surface impoundments. 

Electric utilities retain ownership and control over these existing CCR units, just as hazardous 

waste facilities retain ownership and control over the closed units subject to post-closure 

permitting. In both situations, EPA requirements are designed to address both the existing and 

future risks of further “releases” or “leaking” from these units—i.e., further disposal, as that term 

is defined in section 1004. 

Similarly, in Power Engineering the court considered whether under section 3008 of 

RCRA EPA could bring an action to compel the operator of a metal refinishing plant to comply 

with the state’s RCRA regulations relating to financial assurance.42 10 F. Supp.2d at 1159. The 

defendants argued that since they were not currently disposing of waste, they were operating in 

compliance with state regulations and were exempt from financial assurance requirements. The 

court disagreed. It held that the use of the word "leaking" in the definition of "disposal" 

indicated that the leaching of hazardous waste into the groundwater constitutes the continuing 

disposal of hazardous waste. Id. at 1159-60 (“Because the definition of "disposal" includes the 

word "leaking," disposal occurs not only when a solid waste or a hazardous waste is first 

deposited onto ground or into water, but also when such wastes migrate from their initial 

disposal location.”). 

 

42 Under RCRA’s financial assurance regulations, owners and operators of hazardous waste facilities must 

document that they have sufficient resources to close their facilities and pay third-party claims that may 

arise.
Document submitted to conclude E.O.12866 Review

156

Courts in several circuits have also considered whether the passive migration of 

previously dumped waste constitutes a current or ongoing violation of RCRA, i.e., illegal 

“disposal,” under the citizen suit provisions of section 7002(a)(1)(A). Most have concluded that 

it does. See, Scarlett & Associates v Briarcliff Center Partners, 2009 WL 3151089 (N.D. Ga 

2009)(deciding to “follow the majority rule” and holding that “the continued presence of 

migrating waste constitutes a continuing violation under the RCRA” ); Marrero Hernandez v. 

Esso Standard Oil Co., 597 F. Supp. 2d 272, 283 (D.P.R. 2009) (holding that unremedied, 

migrating contamination is not a wholly past violation); Cameron v. Peach County, GA, No. 

5:02-CV-41-1 (CAR), 2004 WL 5520003 (M.D. Ga. 2004) (holding that the continued presence 

of illegal contamination that remains remedial constitutes a continuing violation, even though the 

acts of unlawful disposal occurred in the past); California v M&P Investments, 308 F.Supp2d 

1137, 1146-1147 (E.D. CA 2003)(Allowing RCRA 7002 claim of continuing violation to 

proceed on evidence that wastes “continue to exist unremediated” as a result of improper 

discharge that had ceased over 20 years prior to filing of suit); Aurora National Bank v TriStar 

Marketing, 990 F. Supp. 1020, 1025 (N.D. Ill. 1998) ("Although subsection (a)(1)(A) does not 

permit a citizen suit for wholly past violations of the statute, the continued presence of illegally 

dumped materials generally constitutes a 'continuing violation' of the RCRA, which is cognizable 

under § 6972(a)(1)(A).") (internal citation omitted); City of Toledo v. Beazer Materials & Servs., 

Inc., 833 F. Supp. 646, 656 (N.D. Ohio 1993) (“[T]he disposal of wastes can constitute a 

continuing violation so long as no proper disposal procedures are put into effect or as long as the 

waste has not been cleaned up and the environmental effects remain remediable."); Gache v. 

Town of Harrison, 813 F. Supp. 1037, 1041-42 (S.D.N.Y. 1993) ("The environmental harms do 

not stem from the act of dumping when waste materials slide off the dump truck but rather after
Document submitted to conclude E.O.12866 Review

157

they land and begin to seep into the ground, contaminating soil and water. So long as wastes 

remain in the landfill threatening to leach into the surrounding soil and water, a continuing 

violation sure may exist."); Acme Printing Ink Co. v. Menard, Inc., 812 F. Supp. 1498, 1512 

(E.D. Wisc. 1992) ("RCRA includes in its broad definition of 'disposal' the continuous leaking of 

hazardous substances.... Accordingly, leaking of hazardous substances may constitute a 

continuous or intermittent violation of RCRA."); Fallowfield Dev. Corp. v. Strunk, No. 89-8644, 

1990 WL 52745 (E.D. Pa. 1990) (“If a person disposes of hazardous waste on a parcel of 

property, the hazardous waste remains in that property insidiously infecting the soil and 

groundwater aquifers. In other words, the violation continues until the proper disposal 

procedures are put into effect or the hazardous waste is cleaned up."). It is particularly notable 

that these cases were all decided under subsection (A); in contrast to subsection (B), section 

7002(a)(1)(A) does not include any reference to liability for past actions or for prior owners. 

Compare, 42 U.S.C. §§ 6972(a)(1)(A) and (B). In reaching their holdings, therefore, the courts 

necessarily relied [solely] on the reach of the statutory definition of “disposal,” which is at the 

heart of EPA’s authority to regulate inactive CCR surface impoundments. 

Courts have also addressed the limits of RCRA’s definition of "disposal" is in the context 

of an EPA action under RCRA section 7003. Section 7003 authorizes EPA to obtain injunctive 

relief for actions, including disposal that “may present an imminent and substantial 

endangerment to health or the environment." 42 U.S.C. § 6973(a). Several courts have evaluated 

whether an inactive disposal site, where no affirmative acts of disposal are occurring, constitute 

an "imminent and substantial endangerment" under this provision. Once again, most courts 

accept a definition of disposal that encompasses leaking or contaminant migration from 

previously discarded wastes. See United States v. Price, 523 F. Supp. 1055, 1071 (D.N.J. 1981), 
Document submitted to conclude E.O.12866 Review

158

aff'd United States v. Price, 688 F.2d 204 (3rd Cir. 1982) (“There is no doubt, however, that 

[section 70003] authorizes the cleanup of a site, even a dormant one, if that action is necessary to 

abate a present threat to the public health or the environment.”) citing S. Rep. No. 96-848, 96th 

Cong., 2d Sess., at 11 (1980); H. R. Rep. 96-1016 (Part I), 96th Cong., 2nd Sess., at 21 reprinted 

in [1980] U.S. Code Cong. & Ad. News, 6119, 6124; United States v. Waste Indus., 734 F.2d 

159 (4th Cir. 1984) (Rejecting district court interpretation that disposal only includes "active 

human conduct" based on the inclusion of "leaking" in the definition of disposal, and interpreting 

the “movement of the waste after it has been placed in a state of repose [to be] encompassed in 

the broad definition of disposal”); United States v. Diamond Shamrock Corp., 12 Envtl. L. Rep. 

20819, 20821 (N.D. Ohio May 29, 1981) (noting that "a disposal clearly requires no active 

human conduct"); United States v. Conservation Chemical Co., 619 F. Supp. 162, 200 (D. Mo. 

1985) ("'disposal' occurs...when [wastes] migrate from their initial location"). See also S.Rep. 

98-284, p 58 (98th Cong. 1st Sess)(“The Environmental Protection Agency and the Department of 

Justice have used the equitable authority and [sic] granted in section 7003 to seek court orders 

directing those persons whose past or present acts have contributed to or are contributing to the 

existence of an imminent and substantial endangerment to abate such conditions. This has been 

an intended use of the section 7003 since 1976....An[sic] evidenced by the definition of 

‘disposal in section 1004(3), which includes the leaking of hazardous wastes, section 7003 has 

always provided the authority to require the abatement of present conditions of endangerment 

resulting from past disposal practices, whether intentional or unintentional.”).

While EPA continues to maintain that the statutory definition of disposal does in fact 

authorize regulation of inactive CCR surface impoundments, this is not the sole basis for that 

authority. Under section 1008(a)(3), EPA is authorized to establish criteria governing solid 
Document submitted to conclude E.O.12866 Review

159

waste management, which includes the “storage” of solid waste. 42 U.S.C. §§ 6904(28) and 

6908(a)(3). RCRA’s definition of “storage” is limited to hazardous waste; under subtitle D, 

therefore, the definition Congress intended was the dictionary definition, which incontrovertibly 

covers the activities associated with continuing to maintain CCR in inactive surface 

impoundments. For example, Miriam Webster defines “storage” as “the state of being kept in a 

place when not being used” and “the act of putting something that is not being used in a place 

where it is available, where it can be kept safely, etc.” 

Finally, consistent with the proposed rule and the final Regulatory Determination in Unit 

IV.B, the final rule does not apply to CCR that is beneficially used.

6. Beneficial Use

The proposed rule generally distinguished between the disposal of CCR and the 

beneficial use of CCR. Disposal activities would be subject to regulation under one of two 

alternative regulatory schemes. But under either alternative, beneficial use would remain Bevill 

exempt and would not be subject to regulation. The proposal identified specific criteria that 

would be used to distinguish between legitimate beneficial uses of CCR and the disposal of 

CCR. These criteria were largely drawn from the approach contained in the May 2000 Bevill 

Regulatory Determination. The criteria were:

- The material used must provide a functional benefit. For example, CCR in 

concrete increase the durability of concrete—and are more effective in combating degradation 

from salt water; synthetic gypsum serves exactly the same function in wallboard as gypsum from 

ore, and meets all commercial specifications; CCR as a soil amendment adjusts the pH of soil to 

promote plant growth. 
Document submitted to conclude E.O.12866 Review

160

- The material substitutes for the use of a virgin material, conserving natural 

resources that would otherwise need to be obtained through practices, such as extraction. For 

example, the use of FGD gypsum in the manufacture of wallboard (drywall) decreases the need 

to mine natural gypsum, thereby conserving the natural resource and conserving energy that 

otherwise would be needed to mine natural gypsum; the use of fly ash in lieu of Portland cement 

reduces the need for cement. CCR used in road bed replace quarried aggregate or other industrial 

materials. 

- Where relevant product specifications or regulatory standards are available, the 

materials meet those specifications, and where such specifications or standards have not been 

established, they are not being used in excess quantities. For example, when CCR is used as a 

commercial product, the amount of CCR used is controlled by product specifications, or the 

demands of the user. Fly ash used as a stabilized base course in highway construction is part of 

many engineering considerations, such as the ASTM C 593 test for compaction, the ASTM D 

560 freezing and thawing test, and a seven day compressive strength above 2760 (400 psi). If 

excessive volumes of CCR are used—i.e., greater than were necessary for a specific project,—

that could be grounds for a determination that the use is not beneficial, but rather is being 

disposed of. 75 FR 35162-35163.

EPA explained that in the case of agricultural uses, CCR would be expected to meet 

appropriate standards, constituent levels, prescribed total loads, application rates, etc. EPA has 

developed specific standards governing agricultural application of biosolids. While the 

management scenarios differ between biosludge application and the use of CCR as soil 

amendments, EPA stated that the Agency would consider application of CCR for agriculture uses 
Document submitted to conclude E.O.12866 Review

161

not to be a legitimate beneficial use if they occurred at constituent levels or loading rates greater 

than EPA’s biosolids regulations allow. (75 FR 35162 – 35163, June 21, 2010)

EPA proposed to codify these criteria in the term, “beneficial use of coal combustion 

products (CCPs).” This definition stated that the beneficial use of CCPs was “the use of CCPs 

that provides a functional benefit; replaces the use of an alternative material, conserving natural 

resources that would otherwise need to be obtained through practices such as extraction; and 

meets relevant product specifications and regulatory standards (where these are available). CCPs 

that are used in excess quantities (e.g., the field-applications of FGD gypsum in amounts that 

exceed scientifically-supported quantities required for enhancing soil properties and/or crop 

yields), placed as fill in sand and gravel pits, or used in large scale fill projects, such as 

restructuring the landscape, are excluded from this definition.” (75 FR 35129 – 35130, June 21, 

2010). 

Commenters generally supported the criteria in the proposal but raised concern that the 

criteria lacked specificity; some commenters stated that the criteria were those that States already 

considered in doing their beneficial use determination. Commenters also suggested the use of a 

“no toxics” provision and others suggested that the criteria include a requirement that 

“environmental benefits” be achieved. A more general comment raised by several commenters 

was that the proposed criteria failed to establish any standard that ensured protection of human 

health and the environment. Finally, one commenter raised concern that EPA’s approach to 

beneficial use, and particularly to large scale fill operations, inappropriately assumed that these 

operations constituted the disposal of solid waste, which, the commenter claimed was 

inconsistent with a series of judicial decisions. 
Document submitted to conclude E.O.12866 Review

162

There are generally three critical issues in determining whether a material is regulated 

under RCRA subtitle D: whether the material is a “solid waste,” whether the activity constitutes 

“disposal,” and whether regulation of the disposal is warranted. Although there can be some 

overlap between these issues in that the same facts may be relevant to each of them, 

understanding the distinction between them is critical to understanding the final approach to the 

beneficial use of CCR adopted in this rulemaking. 

In order to be subject to RCRA, the material must be a solid waste. The statute defines a 

solid waste as “any garbage, refuse... and other discarded material....” 42 U.S.C. § 6903(27). 

As EPA noted in the proposed rule, for some beneficial uses, CCR is a raw material used as an 

ingredient in a manufacturing process that have never been ‘‘discarded,’’ and thus, would not be 

considered solid wastes under the existing RCRA regulations. For example, synthetic gypsum is 

a product of the FGD process at coal-fired power plants. In this case, the utility designs and 

operates its air pollution control devices to produce an optimal product, including the oxidation 

of the FGD to produce synthetic gypsum. In this example, after its production, the utility treats 

FGD as a valuable input into a production process, i.e., as a product, rather than as something 

that is intended to be discarded. Wallboard plants are sited in close proximity to power plants for 

access to raw material, with a considerable investment involved. Thus, FGD gypsum used for 

wallboard manufacture is a product rather than a waste or discarded material. This use and 

similar uses of CCR that meet product specifications would not be regulated under the final rule. 

However, this does not describe the majority of CCR, which are unambiguously wastes; 

after generation in the boiler, they are placed into landfills or surface impoundments. While they 

may subsequently be dredged from these units and reused, placement in a landfill or surface 

impoundment presents prima facie evidence of discard. At the time the material is placed into 
Document submitted to conclude E.O.12866 Review

163

the unit, the utility is not treating the material as a valuable product or otherwise seeking to 

protect the material for use. Although the material may subsequently be reused if a buyer is 

found, the material is originally placed in the unit with the intent to let it remain in place if no 

buyer is found. The waste designation does not change merely because a material in a surface 

impoundment or landfill may in the future be beneficially reused. 

For those materials that are “wastes” the second issue becomes relevant: whether the 

activities involved with the material constitutes “disposal” or “solid waste management.” The 

statue distinguishes between these activities and “use;” several activities are listed in the 

definitions of “disposal” and “solid waste management” and “use” is not among them. See 42 

U.S.C. § 6903(3) and (28). In general, commenters agreed that the three criteria in the proposal, 

and discussed above, would identify those activities that were properly considered to be 

legitimate beneficial uses rather than disposal. As several commenters noted, many state 

beneficial use programs rely on similar (or identical) criteria. And for encapsulated uses, EPA 

agrees that these three criteria are sufficient to distinguish between the activities that will be 

regulated as disposal under this final rule and those that will be considered beneficial use. 

Accordingly, EPA has adopted them in the final definition of “beneficial use.” 

But as EPA acknowledged in the proposal, the issues are more difficult with regard to 

unencapsulated uses. Because these uses involve the direct placement of CCR on the land, they 

are clearly more analogous to activities that have consistently been considered to be “disposal.” 

RCRA defines disposal to specifically include the “placing of any solid waste or hazardous waste 

into or on any land or water so that such solid waste or hazardous waste or any constituent 

thereof may enter the environment...” 42 U.S.C.§ 6903(3). The issue is further complicated by 

the fact that there can be risks associated with placement of unencapsulated CCR on the land. As 
Document submitted to conclude E.O.12866 Review

164

described in the proposal, CCR can leach toxic metals at levels of concern. The major risks 

associated with the placement of unencapsulated CCR on the land for beneficial use involved 

using large volumes of CCR to restructure the landscape, such as occurred at the Battlefield golf 

course, and placement in quarries and sand and gravel pits, such as occurred at the Gambrills, 

Maryland site. EPA acknowledged in the proposal that these types of operations would be 

subject to regulation as disposal, and so were not directly on point. However, because these 

damage cases involved the placement of unencapsulated CCR on the land, they raised questions 

regarding the safety of other uses of unencapsulated CCR that involved direct placement on the 

land. In addition, previous risk analyses do not address many of the use applications currently 

being implemented, and have not addressed the improved leachate characterization methods. 

EPA also noted that some scientific literature indicates that the uncontrolled (i.e., excessive) 

application of CCR can lead to the potentially toxic accumulation of metals.43

As noted, several commenters raised concern that EPA’s beneficial use criteria did not 

include any standard that ensured protection of human health and the environment. EPA agrees 

that a criterion that accounted for the potential risks of the land placement of unencapsulated 

CCR would be an appropriate element to include in differentiating between disposal and 

beneficial use. RCRA’s definition of disposal includes some elements related to risk: 

specifically, the definition includes as a relevant concept that the waste or any constituent of 

concern “may enter the environment.” In this regard it is also relevant that not all disposal 

 

43 See, for example, ‘‘Effects of coal fly ash amended soils on trace element uptake in plant,’’ S.S. Brake, R.R. 

Jensen, and J. M. Mattox, Environmental Geology, November 7, 2003 available at 

http://www.springerlink.com/content/ 3c5gaq2qrkr5unvp/fulltext.pdf; See information regarding the Town of Pines 

Groundwater Plume at http://www.epa.gov/ region5superfund/npl/sas_sites/INN000508071.htm. Also see additional 

information for this site at http://www.epa.gov/ region5/sites/pines/#updates.
Document submitted to conclude E.O.12866 Review

165

activities are regulated by EPA under subtitle D; rather, EPA only regulates those that present 

risks that exceed the Agency’s acceptable risk levels. 

Building off of these concepts, the Agency has developed an additional criterion to 

address both the question of whether the activity is appropriately considered to be “disposal,”

and the question of whether that “disposal” warrants regulation. Because uses that fail to meet 

the beneficial use criteria will be considered disposal and would therefore be considered disposal 

subject to the final regulation, this fourth criterion was designed to exclude uses likely to present 

the same risks as the management practices regulated under other sections of the final rule. 

Thus, the final criterion directly correlates to the practices and the risks that the disposal 

regulations are designed to address: the risks associated with the placement of large quantities of 

CCR in a single concentrated location, such as a CCR landfill, as documented in the 2014 risk 

assessment and the damage cases. 

As discussed in more detail below, to be considered a “beneficial use,” prior to initiating 

an activity that involves placing unencapsulated CCR on the land in amounts greater than 12,400 

tons, in non-roadway applications, the user must demonstrate that environmental releases to 

groundwater, surface water, soil and air are comparable to or lower than those from analogous 

products made without CCR, or that environmental releases to ground water, surface water, soil 

and air will be at or below relevant regulatory and health-based benchmarks for human and 

ecological receptors during use. 

EPA acknowledges that there may be risks associated with uses that are below this 

threshold, depending on the characteristics of the CCR, the amount of material and the manner in 

which it is placed, and (perhaps most important) the site conditions. Consequently, all 

unencapsulated uses, including use in road construction and agriculture, should be conducted 
Document submitted to conclude E.O.12866 Review

166

with care, according to appropriate management practices, and with appropriate characterization 

of the material and the site where the material will be placed. However, as discussed in the 

previous section, because the amounts and, in some cases, the manner in which the CCR are used 

are very different from the land disposal modeled in the risk assessment, EPA cannot extrapolate 

from the risk assessment to reach conclusions regarding the risks these uses may pose. And in 

the absence of such information, EPA cannot establish criteria to regulate these uses.

a. Final Definition of the Term “Beneficial Use of CCR” 

The final beneficial use criteria are as follows: (1) The CCR must provide a functional 

benefit; (2) The CCR must substitute for the use of a virgin material, conserving natural 

resources that would otherwise need to be obtained through practices such as extraction; (3) The 

use of CCR must meet relevant product specifications, regulatory standards, or design standards 

when available, and when such standards are not available, CCR are not used in excess 

quantities; and (4) When unencapsulated use of CCR involves placement on the land of 12,400 

tons or more in non-roadway applications, the user must demonstrate and keep records, and 

provide such documentation upon request, that environmental releases to ground water, surface 

water, soil and air are comparable to or lower than those from analogous products made without 

CCR, or that environmental releases to ground water, surface water, soil and air will be at or 

below relevant regulatory and health-based benchmarks for human and ecological receptors 

during use. Any use that fails to comply with all of the relevant criteria will be considered to be 

disposal of CCR, subject to all of the requirements in the disposal regulations, and the user will 

be considered to be the owner or operator of a CCR disposal unit. Encapsulated uses need only 

comply with the first three criteria. Unencapsulated uses involving placement on the land of 

12,400 tons or more in non-roadway applications that fail to meet all of the beneficial use criteria 
Document submitted to conclude E.O.12866 Review

167

are considered a CCR landfill. As previously noted, the first three criteria were discussed in the 

proposal and commenters generally supported these criteria, which establish flexible 

performance standards. As discussed above, the Agency has developed an additional criterion in 

response to comments, which generally reflects the issues discussed in the proposal. This 

additional criterion is designed to address the environmental and human health concerns 

associated with large-scale, unencapsulated uses that have features similar to landfills. These 

four criteria are discussed in greater detail in the sections below. Any user of CCR that, at a later 

time, believes that there could be a health or environmental issue associated with their beneficial 

use should work with their State Agency to address any potential issue. 

As noted above, encapsulated uses of CCR must only comply with the first three criteria. 

Encapsulated beneficial uses are those that bind the CCR into a solid matrix that minimizes their 

mobilization into the surrounding environment. Examples of encapsulated uses include, but are 

not limited to: (1) Filler or lightweight aggregate in concrete; (2) A replacement for, or raw 

material used in production of, cementitious components in concrete or bricks; (3) Filler in 

plastics, rubber, and similar products; and (4) Raw material in wallboard production. 

Compliance with the first three criteria suffices because, as discussed in Unit IV, the 

available information demonstrates that encapsulated uses of CCR raise minimal health or 

environmental concerns. The Agency did not receive any data to contradict this assessment 

during any of the comment periods. In addition, since publication of the proposal, the Agency 

conducted a study of FGD gypsum in wallboard and fly ash concrete, which further supports this 

conclusion. This study “Coal Combustion Residual Beneficial Use Evaluation: Fly Ash 

Concrete and FGD Gypsum Wallboard” (February 2014) concluded that “environmental 

releases of constituents of potential concern (COPCs) from CCR fly ash concrete and FGD 
Document submitted to conclude E.O.12866 Review

168

gypsum wallboard during use by the consumer are comparable to or lower than those from 

analogous non-CCR products, or are at or below relevant regulatory and health-based 

benchmarks for human and ecological receptors.” 

Criteria 1: CCR must provide a functional benefit. This criterion is designed to ensure 

that the material performs a genuine function in the product or use; while it need not improve 

product performance when compared to the material for which it is substituting, CCR must 

genuinely be a necessary component of the product. In other words, there must be a legitimate 

reason for using CCR in the product other than the fact that it is an alternative to disposal of the 

material, e.g., the material fulfils material specifications. For example, CCR provides a 

functional benefit when used as a replacement for cement in concrete because the CCR increase 

the durability of the concrete and are also more effective against degradation from salt water. 

FGD gypsum serves the same function in the production of wallboard as gypsum mined from 

ore, and meets all product specification. Additionally, CCR can be used to adjust the pH of soils 

thereby increasing and promoting plant growth. 

One commenter noted that many States already consider whether the material provides a 

functional benefit when making beneficial use determinations under their regulatory programs. 

The Agency agrees that this is an important criterion in determining whether a use is a 

“beneficial use.” To the extent that a state regulatory program has determined that a particular 

use provides a functional benefit, this may serve as evidence that this criterion has been met. 

Criteria 2: CCR must substitute for the use of a virgin material, conserving natural 

resources that would otherwise need to be obtained through practices, such as extraction. This 

criterion is intended to ensure that the use is truly “beneficial” from an environmental 

perspective. Examples of CCR used as a substitute for a virgin material include FGD gypsum 
Document submitted to conclude E.O.12866 Review

169

for mined gypsum and the use of fly ash in lieu of Portland cement thereby reducing the need for 

cement. The use of FGD gypsum in the manufacture of wallboard reduces the need to use virgin 

gypsum from mined ore, thereby conserving natural resources (virgin gypsum) while conserving 

valuable energy that would be needed to mine the virgin gypsum. Similarly, the use of CCR fly 

ash in lieu of Portland cement reduces the overall need for cement. CCR used in a road bed 

application substitutes for the use of quarried natural materials that provide structural support for 

the road surface. 

One commenter again highlighted that many states consider this criterion in their current 

state beneficial use programs. The Agency agrees that this second criterion is appropriate, and 

that conserving natural resources is an important function that should be encouraged. Here as 

well, potential users of CCR materials may choose to rely on a state determination to provide 

evidence that this criterion has been met. 

Criteria 3: The use of CCR must meet relevant product specifications, regulatory 

standards, or design standards, when available, and where such specifications or standards have 

not been established, CCR may not be used in excess quantities. This criterion was intended to 

address both the legitimacy of the use and the potential environmental and human health 

consequences associated with the use of excess quantities of CCR, particularly unencapsulated 

CCR. If excessive volumes of CCR are used—i.e., greater than necessary for a specific 

project—that calls into question whether the purpose of the application was in fact a sham to 

avoid compliance with the disposal regulations. In addition, the record demonstrates that the 

risks from use of CCR are more likely to be associated with large volumes, particularly for 

unencapsulated uses. 
Document submitted to conclude E.O.12866 Review

170

The Agency has modified this criterion slightly from the proposed rule. The proposed 

rule merely referenced “ relevant product specifications or regulatory standards;” EPA was 

concerned that this was too narrow, and might not incorporate all of the relevant technical 

information currently available that provides guidance on what constitutes an excess amount. 

Consequently, in the final definition the Agency has added the phrase “design standards.” 

Design standards are different from product specifications, because they include things other 

than “products.” An example of a “design standard” would be technical guidance specifying that 

six inches of CCR is to be used in constructing a road. 

EPA received several comments on this provision, several of which criticized the sole 

reliance on engineering performance standards. For example, one commenter questioned how 

the Agency would quantify acceptable amounts for each use if no specifications or standards 

were in place. One commenter stated that the Agency needs to rely on more than the existence 

of engineering performance standards or comparisons to typical application rates of mined 

materials as coal combustion wastes are unique materials and comparisons to typical rates of 

application of natural gypsum or other soil amendments are inappropriate. Another commenter 

suggested a provision that would require users to follow a plan to only use what is necessary to 

reach the desired effect, in lieu of product specifications. 

EPA purposely did not attempt to establish product specifications for each potential 

beneficial use application. The potential products are too varied, and in many instances EPA 

lacks the necessary expertise (e.g., to develop manufacturing specifications for individual 

products.). Nor is such an approach necessary. When CCR substitute for other materials, the 

amount used is typically controlled by product specifications, particularly for encapsulated uses. 

Product specifications currently exist for many, if not most, of the significant uses of CCR and 
Document submitted to conclude E.O.12866 Review

171

can be found in a variety of sources. For example, as previously described, fly ash used as a 

stabilized base course in highway construction is subject to both regulatory standards under 

DOT/FHA, and engineering specifications, such as the ASTM C 593 test for compaction, the 

ASTM D 560 freezing and thawing test, and a seven day compressive strength above 2760 (400 

psi). 

Similarly, in an agricultural setting, EPA expects all appropriate standards, constituent 

levels, prescribed total loads, and application rates to be met. For example, EPA has developed 

specific standards governing the agricultural application of biosolids. While the management 

scenarios differ between biosludge application and the use of CCR as soil amendments, EPA 

would consider application of CCR for agriculture uses not to be a legitimate beneficial use if 

they occurred at constituent levels or loading rates greater than EPA’s biosolids regulations. 

Several commenters also noted that agronomic rates currently exist for certain items such as 

peanuts, cotton, tomatoes, corn and soybeans.44 EPA would generally consider application of 

CCR above these rates, or any other rate that has been scientifically justified, to constitute 

disposal rather than beneficial use. 

Many other sources of technical reports and documents exist for other uses. ASTM 

Standard E2277-03 provides standard guidance and a methodology for using CCR in a structural 

fill and includes a consideration of engineering properties and behaviors, testing procedures, and 

design considerations relevant to constructing a structural fill project using CCR. Industry 

guidance, such as USWAG’s “Engineering and Environmental Guidance on the Beneficial Use 

of Coal Combustion Products in Engineered Structural Fill Projects”, may also provide 

 

44 Commenters argued that, at least in agronomic settings, there is no incentive to use excess amounts 

because it simply increases the grower’s cost. 
Document submitted to conclude E.O.12866 Review

172

information relevant to this issue. Further, some states, such as Wisconsin and Virginia, have 

developed environmental guidance for evaluating the suitability of a site prior to construction of 

a CCR structural fill. 

While many of these documents do not establish binding requirements—nor is EPA 

seeking to make them binding on users--they provide evidence of the design and construction 

practices, including the amounts, that are typically used throughout the industry, and provide a 

basis on which to evaluate whether excessive quantities have been used in a particular 

application. These types of documents are also relevant in making judgments on the larger 

question—whether the activity is legitimate reuse or merely sham disposal. In essence, product 

specifications serve the same function as the requirement suggested by a commenter for a plan to 

only use what is necessary to reach the desired effect.

Commenters were also concerned that the proposed standards, and particularly this 

criterion, did not include any provision that would ensure that CCR reuse was protective of 

human health and the environment. One commenter stated that product specifications and 

engineering standards do not speak to environmental risk or consumer exposure. This same 

commenter was concerned that the proposed criteria used circular logic by stating that excess 

materials were not to be used in cases where specifications or standards have not been 

established. Another commenter criticized this criterion because it did not include threshold 

levels that protect public health from the range of toxicants routinely found in coal ash. 

EPA generally disagrees that the requirement to ensure that excessive volumes have not 

been used is unrelated to environmental and safety concerns. Minimizing the amount of material 

used in a product or released to the environment decreases potential exposures to the material. 

EPA agrees, however, that an additional criterion that more directly addresses the potential 
Document submitted to conclude E.O.12866 Review

173

health and environmental risks is appropriate for unencapsulated uses, which present the greater 

potential for exposures of concern. As discussed in more detail below, the Agency has added a 

criterion to specifically require users of unencapsulated CCR to demonstrate that environmental 

and health related standards have been met. The criterion is a general performance standard that 

is equally applicable to all sites and uses and will account for a wide variety of potential 

exposures. By contrast, in order to establish toxicant “threshold levels,” EPA would need to 

develop risk assessments that account for the wide variety of potential uses and exposures. This 

is neither practical nor feasible, given the site specific nature of the potential risks and the myriad 

of potential uses. In addition, EPA disagrees that this is necessary, as the performance standard 

laid out in the fourth criterion will appropriately address the risks documented in the current 

record for these uses. Furthermore, as the Agency has previously stated in the May 2000 

Regulatory Determination and the 2010 proposal, leaving the Bevill determination in place for 

beneficial use does not conflict with EPA’s view that certain beneficial uses, e.g., use in road 

construction and agriculture, should be conducted with care, according to appropriate 

management practices, and with appropriate characterization of the material and the site where 

the materials will be placed. EPA has concluded that the potential risks of these uses do not 

warrant federal regulation, but can be addressed, if necessary, in other ways. State programs 

exist and have the expertise to address beneficial use applications. In addition, the Agency is 

currently developing a Framework to address the risks associated with the beneficial use of 

unencapsulated materials. This Framework is expected to be finalized in 2015; the Framework 

will be available to assist in the implementation of issues associated with the unencapsulated 

uses of CCR. The Agency has also been working with USDA to address the risks associated 

with the agricultural use of CCR. In conclusion, the Agency believes that sufficient tools are 
Document submitted to conclude E.O.12866 Review

174

available (or will soon be available) to address the site-specific risks associated with the 

beneficial use of CCR. 

Criteria 4: When unencapsulated use of CCR involving placement on the land of 12,400 

tons or more in non-roadway applications, the user must demonstrate and keep records, and 

provide such documentation upon request, that environmental releases to ground water, surface 

water, soil and air are comparable to or lower than those from analogous products made 

without CCR, or that environmental releases to ground water, surface water, soil and air will be 

at or below relevant regulatory and health-based benchmarks for human and ecological 

receptors during use. The Agency has established an environmental criterion to protect human 

health and the environment in response to numerous comments received on the proposal raising 

concern that additional provisions were necessary to ensure that unencapsulated uses of CCR

needed to be conducted in an environmentally protective manner. The Agency discussed in the 

proposed rule the ways in which the use of CCR in an unencapsulated manner could affect 

ground water, surface water, air and be associated with dust emissions. This fourth 

“environmental” criterion requires potential users to addresses potential risks from all of these 

pathways in order to avoid compliance with the final disposal requirements. Existing sources of 

guidance and standards (e.g., ASTM E2277-03 and USWAG’s “Engineering and Environmental 

Guidance on the Beneficial Use of Coal Combustion Products in Engineered Structural Fill 

Projects,” to name just two that are currently available), are available and may provide useful 

assistance for determining if the use of CCR are comparable to or lower than those from 

analogous products made without CCR, or that environmental releases to ground water, surface 

water, soil and air will be at or below relevant regulatory and health-based benchmarks for 

human and ecological receptors during use. Information (e.g., modeling results, proposed 
Document submitted to conclude E.O.12866 Review

175

designs, risk assessments, etc.) that have been proposed or developed to comply with state 

standards that explicitly address the environmental impacts of unencapsulated uses may also be 

relevant to this determination.

i. Source of the 12,400 Ton Threshold and Fill Operations.

As discussed earlier in this section, the fourth criterion was designed to address whether 

the activity is appropriately considered to be “disposal” and whether that “disposal” warrants 

regulation. Thus, the final criterion correlates to the practices and the risks at issue: the 

placement of large quantities of CCR in a single concentrated location, as documented by the 

2014 risk assessment and the damage cases. 

In the proposed rule, EPA explained that the risks of greatest concern from 

unencapsulated beneficial uses were associated with the placement of CCR in quarries and sand 

and gravel pits, and with large scale fill operations used to re grade the landscape. EPA 

generally proposed to define these operations as “disposal” rather than “beneficial use.” As 

discussed below, EPA has retained that approach with respect to the placement in sand and 

gravel pits and quarries; consequently the fourth criterion need not account for these uses. By 

contrast, EPA has not definitively concluded that “large scale fill operations,” per se, constitute 

the disposal of CCR. This is because EPA agrees with commenters that, if constructed correctly, 

large scale fill operations can meet all of the criteria for a beneficial use. But EPA also agrees 

that these applications can present risks to human health and the environment, and therefore has 

drafted the fourth criterion to specifically address the risks presented by these operations. The 

fourth criterion is thus tied to the Agency’s general approach to large scale fill. 

The Agency acknowledged in the proposal that additional guidance was warranted on 

what would constitute a large scale fill operation, and received numerous comments on this issue 
Document submitted to conclude E.O.12866 Review

176

in response to the proposal. EPA requested comments again on the topic of large scale fills in a 

Notice of Data Availability (NODA) published in 2013. 78 FR 46940, (August 2, 2013). The 

NODA discussed the fact that many commenters on the proposed CCR rule stated that EPA 

should have developed a size criterion to define large scale fill operations. One commenter 

suggested 5,000 cubic yards as a size criterion for a CCR landfill, but did not provide a basis for 

this. Other commenters suggested size criteria but for different reasons than defining disposal 

criteria; for example, Wisconsin has a standard where all CCR used for unconfined and confined 

“fill projects exceeding 5,000 cubic yards require concurrence by the State prior to 

commencement of the project.” Similarly, West Virginia stated that “unencapsulated use of 

CCR as structural fills not exceeding 10,000 cubic yards are approvable on a case-by-case basis.” 

In the NODA, EPA identified three different types of data sets that could provide 

information relevant to developing appropriate criteria or to otherwise defining what constitutes 

a “large scale” fill operation. EPA solicited comment on the adequacy of the data sets and

whether EPA should consider them for the purpose of creating criteria or a definition. The three 

data sets were: (1) The size of the structural fills that have resulted in damage cases; (2) The 

distribution of landfill sizes, derived either from an EPA Office of Water's questionnaire or from 

the landfill size distribution used in the proposed rule; and (3) The size distribution for large 

scale fills that have been constructed in North Carolina.

Many commenters argued that it was entirely inappropriate for EPA to specify in the rule 

when a project constitutes beneficial use simply by volume or amount of structural fill necessary 

to construct a stable base for a building. Commenters argued that a large scale fill operation, if 

designed appropriately, constituted a legitimate beneficial use. In fact, industry commenters 
Document submitted to conclude E.O.12866 Review

177

universally claimed that they were not aware of any damage cases or adverse environmental 

impacts associated with structural fills that had adhered to industry guidance (e.g., ASTM 

standard E2277-03 for structural fills and the USWAG Engineering and Environmental 

Guidance on the Beneficial Use of CCPs in Engineered Structural Fill Projects), and argued that 

the history of well-designed and implemented engineered structural fills demonstrate that CCR

can serve as a valuable resource in avoiding disturbing native ground to secure borrow soils 

where fill materials are needed to establish a final grade for a project site that meets the need of 

the proposed final use. To this end, the commenters also acknowledged the need for site 

characterization and characterization of the CCR themselves are fundamental to the construction 

of fills across the U.S. Similarly, other commenters stated that size should not be the only 

criterion used to define large scale fill operations and highlighted that the site conditions, 

including such features as the hydraulic conductivity of the area, should also be an important 

criterion to consider. Still other commenters stated that CCR landfills cannot include large scale 

fill CCR beneficial use projects because such operations do not involve disposal of a solid waste. 

Rather, industry commenters argue that the determination as to what is disposal as opposed to 

beneficial use should be a determination that rests solely with State agencies. These commenters 

suggested that the determination as to whether a particular fill project constituted disposal, rather 

than beneficial use should be based on a series of factors, and not simply a size-cut-off. Finally, 

other commenters argued that the Agency incorrectly presumed that only large scale fill 

operations could cause environmental damage, and suggested that rather than regulating large 

scale fill operations solely on the basis of the volume or the amount of CCR involved, the 

information available to EPA from damage cases and monitoring data suggests that an 
Document submitted to conclude E.O.12866 Review

178

additional, if not primary criteria for regulating fill operations, including those involved in 

highway construction, should include the prevention of CCR coming into contact with water. 

Focusing on the risks of concern—that large scale fills were effectively operating as 

landfills--the Agency reviewed the database of landfills used in the 2014 risk assessment and 

has established a threshold limit that corresponds to the smallest size landfill in the risk 

assessment database. EPA selected this threshold as the trigger for requiring an affirmative 

demonstration by the user that there will be no releases of concern as a consequence of the land 

application, because the available evidence in the record (i.e., the 2014 risk assessment) 

demonstrates that at these volumes the potential risks are of such significance to warrant 

regulation. Based on this evidence, the burden then shifts to the potential user to demonstrate 

that these potential risks do not exist at the particular site or have been adequately mitigated. 

Under this approach, unencapsulated beneficial use applications greater than or equal to 12,400 

tons can still be conducted without becoming subject to the disposal regulations by using 

engineering principles, such as a liner system, and demonstrating that environmental releases to 

ground water, surface water, soil and air are comparable to or lower than those from analogous 

products made without CCR, or that environmental releases to ground water, surface water, soil 

and air will be at or below relevant regulatory and health-based benchmarks for human and 

ecological receptors. 

EPA agrees that the volume of CCR involved should not be the sole basis for determining 

whether an operation constitutes disposal. As such, the Agency is requiring the use of the fourth 

criterion in order to address any potential risks associated with unencapsulated uses of CCR that 

are in excess of 12,400 tons. Users will be required to make an affirmative demonstration 

relating to the potential environmental releases and the potential risks of the application (in 
Document submitted to conclude E.O.12866 Review

179

addition to requiring compliance with the other three criteria). Specifically, users will be 

required to demonstrate that environmental releases to ground water, surface water, soil and air 

are comparable to or lower than those from analogous products made without CCR, or that 

environmental releases to ground water, surface water, soil and air will be at or below relevant 

regulatory and health-based benchmarks for human and ecological receptors during use. EPA 

expects such determinations to take into account a wide variety of factors, including the 

hydraulic conductivity of the area, proximity of the material to water, and the likelihood of 

contact with water. EPA also expects that such determinations would take into account, as many 

commenters acknowledged to be appropriate and necessary, the need for site characterization 

and characterization of the CCR.

The fourth criterion was adopted in part, to address commenters’ concern that the EPA 

should include a criterion that prevents the placement of CCR in water sources. These are 

legitimate concerns; existing damage cases show that the placement of CCR in sand and gravel 

pits was almost always associated with CCR being placed in contact with water. The fourth 

criterion will require the user to demonstrate that environmental releases to ground water, surface 

water, soil and air are comparable to or lower than those from analogous products made without 

CCR, or that environmental releases to ground water, surface water, soil and air will be at or 

below relevant regulatory and health-based benchmarks for human and ecological receptors 

during use. As a consequence of this requirement, EPA expects that significant changes may 

need to be made in order to proceed with a proposed use; for example, conducting the required 

assessment, may demonstrate that the only way to achieve the performance standard is to install 

engineering features, such a liner, as part of the proposed project. 
Document submitted to conclude E.O.12866 Review

180

Application of unencapsulated CCR to the land in volumes less than the 12,400 tons will 

not require an affirmative demonstration to be considered a beneficial use. While the Agency 

has sufficient information to document that unencapsulated uses can present a hazard, based on 

the current rulemaking record, EPA lacks the information necessary to demonstrate that 

unencapsulated uses in smaller amounts are likely to present a risk.45 In other words, the 

evidence relating to these uses is not sufficient to shift the burden to the potential user to 

affirmatively demonstrate the safety of the proposed use. Nevertheless, the Agency expects 

potential users of unencapsulated CCR below this threshold to work with the States to determine 

the potential risks of the proposed use at the site and to adopt the appropriate controls necessary 

to address the risks. In this regard, EPA notes that the composition and leaching behavior of 

CCR being beneficially used may change over time due to upgrades in air pollution controls 

devices at coal-fired power plants. Further, initial determinations for existing BU applications 

may have relied on single-point pH test methods (e.g., TCLP, SPLP) that, depending on actual 

field conditions in which the applications are occurring, can under- or over-estimate leachate 

concentrations. Scientific advancements in leach test protocols have found that the degree of 

leaching can vary by several orders of magnitude. Accordingly, States overseeing CCR BU 

programs are encouraged to closely evaluate existing BU applications in light of ongoing 

scientific advances in tools and technologies to ensure these applications remain protective of 

 

45 In November 2014, EPA received reports alleging that extensive groundwater monitoring data collected 

by the Wisconsin Department of Natural Resources demonstrated a correlation between beneficial uses of 

unencapsulated CCR below these thresholds and contaminated drinking water wells in southeastern 

Wisconsin. Insufficient time was available to allow EPA to evaluate these reports as part of this 

rulemaking. However, EPA will continue to evaluate the issues associated with unencapsulated uses of 

CCR, and to the extent available data demonstrate the need for revisions to these criteria, EPA will 

initiate the necessary rulemaking procedures. 
Document submitted to conclude E.O.12866 Review

181

human health and the environment. In addition, the Agency is working to provide assistance to 

states and potential users; this includes the release of the Agency’s Industrial Waste Evaluation 

Model (IWEM), and the development of a Framework for systematically assessing 

unencapsulated BU applications to aid in assessing whether there are environmental risks 

associated with site specific structural fills. 

ii. Exclusion of Roadway Applications from the 4th Criterion 

In the 2010 proposal, the Agency stated that the placement of unencapsulated CCR on the 

land, such as in road embankments, presented concerns, but that the amount and the manner in 

which they are used – subject to engineering specifications and material requirements rather than 

landfilling techniques – are very different from land disposal. The Agency highlighted the 2005 

guidance that was developed by EPA, FHWA, DOE, ACAA, and USWAG, addressing the 

appropriate methodologies and engineering requirements for the use of coal ash in highway 

construction. Lastly, the Agency noted the difference in terms of volume; the difference between 

the amounts of CCR that could be disposed of in a landfill vs. the amount of CCR used in the 

construction of a roadbase (typically on the order of six to twelve inches thick). 

EPA received a number of comments requesting that the definition of a CCR landfill 

exclude CCR used in highway and road construction projects and similar beneficial use projects 

authorized by an appropriate State agency. These commenters reasoned that the “arbitrary 

cutoff’ discussed in the NODA would inappropriately capture such uses. 

The Agency has excluded roadways and associated embankments from the fourth 

criterion because the methods of application are sufficiently different from CCR landfills that 

EPA cannot extrapolate from the available risk information to determine whether these activities 

present similar risks. Roadways are subject to engineering specifications that generally specify 
Document submitted to conclude E.O.12866 Review

182

CCR to be placed in a thin layer (e.g., six to 12 inches) under a road. The placement under the 

surface of the road limits the degree to which rainwater can influence the leaching of the CCR.

There are also significant differences between the manner in which roadways and 

landfills can potentially impact groundwater. These include the nature of mixing in the media, 

the leaching patterns, and how input infiltration rates are generated. First, CCR landfills are 

typically a homogenously mixed system, and as a result, there are no spatial variations of the 

chemical and physical properties of the media (for example, bulk density, hydraulic conductivity 

and contaminant concentration). By contrast, roadways are generally constructed of several 

layers with different material properties (heterogeneity). This difference affects the hydraulic 

conductivity of a mass of CCR in a landfill, as compared to CCR placed in an embankment. Any 

potential leaching will tend to spread over the length of the embankment, as opposed to the

leaching in a downward motion that would occur in a homogenously filled landfill.

Finally, (and perhaps most critically) the construction of roads and associated 

embankments are supervised and approved by State and/or Federal Department of Transportation 

(DOT) engineers who ensure compliance with engineering specifications

While EPA is exempting roadbed applications of 12,400 tons or larger from the fourth 

criterion, EPA is mindful of situations where large quantities of CCR have been used without 

appropriate engineering controls or where placement on the land has apparently far exceeded 

those necessary for the engineering use of the materials. One such situation occurred in Puerto 

Rico with CCR generated by the AES Coal Fired Power Plant in Guayama. As discussed in Unit 

IV.B, CCR and an aggregate created from them (“AGREMAX”) were being used as fill in 

housing developments and in road projects. Over two million tons of this material was used 

between 2004 and 2012. When made aware of the situation, EPA raised concerns over the use of 
Document submitted to conclude E.O.12866 Review

183

CCR and AGREMAX based on the fact that the Environmental Quality Board had not imposed 

engineering controls, specified appropriate uses, or otherwise limited the use of AGREMAX by 

the end users. Inspections of some of the sites where the material had been placed showed use 

in residential areas, areas close to wetlands and surface waters and/or over shallow sole source 

drinking water aquifers. In addition, in some cases the volumes appeared to be in excess of what 

was necessary for engineering uses and some sites appeared to be abandoned. This kind of 

situation will be directly addressed by the new beneficial use criteria promulgated in the final 

rule. To qualify as a beneficial use, the use of AGREMAX would need to meet all four of the 

criteria – that is, it must provide a functional benefit, substitute for a virgin material, meet 

product specifications, and in this case, the user would be required to make the environmental 

demonstration for the non-roadbed applications.

iii. Kinds of unencapsulated uses of CCR required to comply with the fourth criterion

Unencapsulated uses of CCR are numerous and range, in total use, from hundreds of 

thousands of tons to millions of tons per year. These applications include, as examples, the 

following: (1) flowable fill; (2) structural fills; (3) soil modification/stabilization; (4) waste 

stabilization/solidification; (5) use in agriculture as a soil amendment; and (6) aggregate.

Many of these unencapsulated uses, other than structural fills, are not generally expected 

to be used in amounts that would require an environmental demonstration under the fourth 

criterion. And for several of these applications, which can be structurally very different from 

landfills, EPA expects that even if these applications are used in amounts greater than 12,400 

tons, potential users will be easily able to meet the performance standard. For example, the use 

of CCR for soil modification or stabilization, agriculture, waste stabilization/solidification, 

aggregate or flowable fill applications, is generally not similar to the mounding that occurs in a 
Document submitted to conclude E.O.12866 Review

184

landfill situation. These differences can have a tremendous bearing on the leaching potential of 

the CCR materials. 

Structural fills, however, can be larger applications and so may be required to 

demonstrate compliance with the environmental standards in the fourth criterion more 

frequently. In addition, because structural fills can be similar to the landfills regulated in the 

final disposal rule, some proposed applications may need to install engineering features to meet 

the performance standard. 

iv. Demonstration that “environmental releases to ground water, surface water, soil and air 

are comparable to or lower than those from analogous products made without CCR, or that 

environmental releases to ground water, surface water, soil and air will be at or below relevant 

regulatory and health-based benchmarks for human and ecological receptors during use.”

The environmental fourth criterion requires a potential use of CCR to compare analogous 

products or to perform an environmental assessment evaluating whether releases to the 

environment are at or below relevant regulatory and health-based benchmarks for human and 

ecological receptors during use. A demonstration should consider the development of a 

conceptual model to assist in the determination of whether the environmental criteria contained 

in the definition of the term “beneficial use of CCR” can be demonstrated. Numerous potential 

pathways exist and these should be evaluated as necessary depending on the potential application 

of the CCR. Potential exposure pathways include exposure to ground water, surface water, air, 

and soils. Generation of dust, leaching to ground water and surface water, inhalation of mercury, 

and plant uptake are areas that need to be evaluated. A complete evaluation of the types of 

releases, the types of exposure and the receptors that may be potentially affected by a potential 

application will need to be conducted. A screening comparison will need to be performed 
Document submitted to conclude E.O.12866 Review

185

comparing the concentrations of individual constituents of potential concern to the following 

benchmarks: human soil ingestion, ecological soil, tap water ingestion, fish ingestion, surface 

water, sediment, and inhalation. As an example, a user could compare a mercury concentration 

to a human health screening benchmark with an inhalation value of 300 ng/m3. Existing 

documents that can be used to gain an understanding of conceptual models, pathways and 

regulatory limits include: Risk Assessment Guidance for Superfund, Exposure Factors 

Handbook, Volumes I, II and III, Risk Assessment Guidance for Superfund Volume I: Human 

Health Evaluation Manual Part A, Industrial Waste Management Model (IWEM) Technical 

Backgrounds Document, Exposure Factors Handbook, Human and Ecological Risk Assessment 

of Coal Combustion Wastes. In addition, although it is not directly applicable, a potential user of 

unencapsulated CCR may find it useful to consult the previously mentioned “Coal Combustion 

Residual Beneficial Use Evaluation: Fly Ash Concrete and FGD Gypsum Wallboard” and the 

“Methodology for Evaluating Encapsulated Beneficial Uses of Coal Combustion Residuals” to 

assist in the determination of whether the unencapsulated CCR is comparable to or lower than 

those from analogous products made without CCR, or that environmental releases to ground 

water, surface water, soil and air will be at or below relevant regulatory and health-based 

benchmarks for human and ecological receptors during use.

After the effective date of the final rule, any potential user of CCR that makes the 

demonstration in the fourth criterion must keep records and provide such documentation upon 

request.. 

b. Placement in Sand and Gravel Pits and Quarries

EPA proposed that, without exception, unencapsulated CCR placed in sand and gravel 

pits, and quarries should not constitute beneficial use, but disposal. The Agency highlighted a 
Document submitted to conclude E.O.12866 Review

186

number of damage cases that involved the filling of old, unlined quarries or gravel pits with large 

quantities of unencapsulated CCR, under the guise of “beneficial use.” Because of the damage 

cases and the concern that in such instances, sand and gravel pits and quarries were essentially

operating as landfills, EPA proposed to define the placement of CCR in sand and gravel pits or 

quarries as land disposal that would be subject to regulation under either of the proposed 

regulatory options. The proposal specifically defined a CCR landfill as “a disposal facility or 

part of a facility where CCR are placed in or on land and which is not a land treatment facility, a 

surface impoundment, an underground injection well, a salt dome formation, a salt bed 

formation, an underground mine, a cave, or a corrective action management unit. For purposes 

of this part, landfills also include piles, sand and gravel pits, quarries, and/or large scale fill 

operations. Sites that are excavated so that more coal ash can be used as fill are also considered 

CCR landfills.” 

Commenters representing the environmental community and local citizens stated that 

there were numerous examples of harm caused by the unencapsulated “reuse” in sand and gravel 

pits and quarries, which demonstrate that these unencapsulated uses are merely disposal in 

disguise, and must be regulated stringently under Subtitle C of RCRA to prevent the risks they 

pose of contaminating groundwater, surface water, and ecological systems with heavy metals and 

other harmful pollutants. In particular, they argue that “There have already been at least thirteen 

damage cases caused by the disposal of coal ash in sand and gravel pits or former quarries that 

led to contamination of water sources and/or ecological damages.” Some states also agreed that 

placement in sand and gravel pits and quarries should not be considered beneficial use. For 

example, one state commenter agreed that CCR placement in sand and gravel pits and quarries is 

“disposal” and not beneficial use while another state commenter wrote that it concurs that large-
Document submitted to conclude E.O.12866 Review

187

scale fills in quarries in poorly engineered applications can cause negative impacts. Industry 

commenters highlighted that damage cases related to sand and gravel pits and quarries were old 

practices that no longer take place. These commenters argued that while sand and gravel 

quarries have been used to dispose of CCR, it is not correct to assume that with proper 

engineering and environmental standards that CCR cannot be used beneficially to reclaim 

quarries for uses such as recreational areas, commercial or industrial uses, or to aesthetically 

improve the characteristics of the land. 

EPA is finalizing its proposal that placement of CCR in sand and gravel pits constitutes 

disposal, rather than beneficial use. The final definition of a CCR landfill explicitly includes 

placement of CCR in sand and gravel pits and quarries. EPA has adopted this approach because 

the practice has resulted in numerous damage cases as a result of the highly permeable strata 

typically present at such sites. Moreover, while the commenters may be correct that “with 

proper engineering measures, placement in sand and gravel pits and quarries can be conducted 

safely”, they submitted no data to support this contention. The only engineering features the 

available information demonstrate would be protective are those that have been determined to be 

necessary for CCR landfills—i.e., composite liners and groundwater monitoring. And in the 

absence of these features, any future placement in sand and gravel pits and quarries could not 

meet the performance standard in the fourth criterion: i.e., that environmental releases to ground 

water, surface water, soil and air will be at or below relevant regulatory and health-based 

benchmarks for human and ecological receptors during use. 

B. Definitions

EPA proposed definitions for a number of key terms used in the proposed subtitle D rule 

that the Agency determined were necessary for the proper interpretation of the proposed 
Document submitted to conclude E.O.12866 Review

188

requirements, e.g., coal combustion residuals, existing CCR landfill. (See 75 FR 35196-97, June 

21, 2010.) In addition, EPA also proposed definitions for terms that were specific to certain 

regulatory requirements, e.g., seismic impact zone.

EPA is finalizing many of the regulatory definitions that were proposed, some with 

modifications. Several definitions that were proposed have been removed because they are no 

longer relevant to this rulemaking and a number of new definitions have been added. 

Specifically, definitions that have been removed from the final rule include: natural water table, 

probable maximum precipitation, surface water, systemic toxicants and upstream toe. 

New definitions are discussed in the technical section of the rule for which they apply. The 

majority of the regulatory definitions contained in the proposed rule have been retained in the 

final rule, as proposed or with minor clarifying changes. These definitions are codified in §

257.53 and include the following: acre foot, active life, aquifer, area capacity curves, areas 

susceptible to mass movement, coal combustion residuals (CCR), displacement, facility, factor of 

safety, fault, freeboard, groundwater, hazard potential classification, high hazard potential 

surface impoundment, significant hazard potential surface impoundment, low hazard potential 

surface impoundment, holocene, hydraulic conductivity, karst terrain, lithified earth material, 

maximum horizontal acceleration in lithified earth material, new CCR landfill, new CCR surface 

impoundment, operator, owner, poor foundation conditions, recognized and generally accepted 

good engineering practices, representative sample, run-off, run-on, sand and gravel pit or 

quarry, seismic impact zone, state, structural components, unstable area, uppermost aquifer, and 

waste boundary. 

Several definitions received a significant number of comments and upon further 

evaluation by EPA have been modified to better explain their meaning or intent. This includes 
Document submitted to conclude E.O.12866 Review

189

the definitions for the following terms: CCR landfill or landfill, CCR surface impoundment or 

impoundment, existing CCR landfill and existing CCR surface impoundment. These comments, 

along with the revisions made in response are discussed in more detail below. In addition, EPA 

has revised a number of definitions, or added new definitions, to be consistent with revisions 

made in the corresponding technical requirements. These are discussed in the various sections of 

the preamble that address the specific technical requirement. For example, as discussed in Unit 

V, EPA has revised the definition of “independent registered professional engineer or 

hydrologist” to “qualified professional engineer” to address the concerns raised in comments. 

1. Definition of CCR landfill

EPA proposed to define a CCR landfill as “a disposal facility or part of a facility where 

CCR is placed in or on land and which is not a land treatment facility, a surface impoundment an 

underground injection well, a salt dome formation, a salt bed formation, an underground mine, a 

cave, or a corrective action management unit. For purposes of this subpart, landfills also include 

piles, sand and gravel pits, quarries, and/or large scale fill operations. Sites that are excavated so 

that more coal ash can be used as fill are also considered CCR landfills.” (See 75 FR 35239.)The 

Agency received a significant number of comments on the proposed definition. These comments 

focused almost exclusively on the inclusion of “large-scale fill operations” and “piles” within the 

definition of CCR landfill. Regarding large-scale fills, commenters argued that one of the 

fundamental problems with the proposed definition was that it assumed all CCR placed in large 

scale fill operations constituted “disposal” of CCR (and that these operations therefore constitute 

CCR landfills) rather than beneficial use. Commenters furthered argued that CCR is often used 

in engineered fills, such as road base and road embankments and that these legitimate beneficial 

use operations should not be subject to the CCR landfill regulations. 
Document submitted to conclude E.O.12866 Review

190

Commenters also argued that “piles” should be omitted from the definition of a CCR 

landfill for a variety of reasons. Several commenters argued that including the word “pile” was 

overly broad and insufficiently prescriptive and would inappropriately capture on-going or shortterm CCR management activities that did not constitute disposal, such as storage for beneficial 

use. These commenters also raised concern that including “piles” in the definition of CCR 

landfill without further clarification or specificity, i.e., when used as part of a beneficial use 

operation, would negatively affect beneficial use activities. Other commenters raised concern 

that the term “piles” was too vague, and suggested that whether piles were treated as CCR 

landfills should be determined by the size of the piles, or the intent for which such piles exist. 

These commenters suggested the Agency should exclude small piles of CCR that are staged 

and/or consolidated prior to transport or placement for disposal. These commenters argued that 

subjecting all CCR piles to all of the landfill requirements was “illogical and inappropriate.”

Certain commenters argued that piles should not be regulated under this rule because they 

do not present a significant risk to the environment, as evidenced by a lack of damage cases. 

Alternately, other commenters suggested that if EPA were to regulate piles, the Agency should 

consider a regulatory strategy other than regulation as a CCR landfill. One alternative regulatory 

strategy suggested was to include an option establishing a limit (e.g., 180 days) on the amount of 

time that the CCR could be allowed to be maintained in a pile without regulation as a CCR 

landfill. Another option suggested was to develop a set of reasonable design and operating 

standards consistent with the uses and risks posed by piles. Such design standards could include 

the requirement for a low permeability underlayment or base such as asphalt, concrete or an 
Document submitted to conclude E.O.12866 Review

191

HDPE liner. Operating standards could include such provisions as labeling, and the requirement 

to remove at least 90 percent of the contents every 90 days, with a full cleanout annually.

EPA believes the suggested option to establish a time limit would be difficult to oversee 

and verify. States and citizens would have no way to determine when CCR is placed in a pile and 

when the CCR was subsequently removed. Therefore, EPA is rejecting this suggested option. 

The suggested option to develop appropriate design and operating standards is essentially the 

approach EPA has adopted, as discussed in more detail below. However, the final design and 

operating standards differ according to the management practices, and include measures to 

control fugitive dust, and for certain practices, require the installation of a composite liner and 

leachate collection system.

EPA discussed its final approach to large-scale fill operations in Unit V.A; the definition 

of a CCR landfill has been revised to be consistent with the approach described in that section. 

As explained at length, EPA has adopted a final approach that distinguishes between beneficial 

use and the “disposal” of CCR. Activities that meet the definition of beneficial use are not 

subject to these regulations. Activities that do not meet all of the criteria in the definition of a 

beneficial use—and in particular, such activities that involve the placement of unencapsulated 

CCR on the land--are considered disposal and are subject to the requirements of this final rule. 

Consistent with this approach the final definition of a CCR landfill has been revised to clarify 

that it includes “the use of CCR that does not meet the definition of a beneficial use of CCR.” 

Waste piles, including those used to temporarily store or manage CCR on-site prior to disposal in 

a CCR landfill or subsequent beneficial use, have been retained within the definition of a CCR 

landfill. In making this determination the Agency was strongly influenced by the similarities in 

the potential risks posed by both waste piles and CCR landfills to human health, groundwater 
Document submitted to conclude E.O.12866 Review

192

resources, or the air if improperly managed. Both CCR piles and CCR landfills are subject to 

external factors such as rain and wind, which can adversely affect human health and the 

environment. For example, uncontrolled run-on and run-off can result in ponding of water in 

and around the unit resulting in increased leachate which has the potential to affect groundwater. 

Similarly, absent dust control measures, such as the conditioning of CCR, both CCR landfills 

and waste piles have the potential to generate significant amount of fugitive dusts. Indeed, CCR 

piles are generally more susceptible to the creation of fugitive dusts. And contrary to the 

commenters’ contention about the absence of damage cases, the single most frequent issue 

presented during the public hearings was the allegation by individual citizens of damage caused 

by fugitive dusts from neighboring CCR facilities. Moreover, the same pollution control 

measures, such as liners, leachate collection systems, and groundwater monitoring, will address 

the potential adverse effects from both of these units. As such, the Agency sees no reason to 

treat piles and landfills differently.

EPA also disagrees that the inclusion of CCR piles would capture on-going or short-term 

CCR management activities that do not constitute disposal. Irrespective of whether the facility is 

using the pile as “temporary storage” or ultimately intends to direct the CCR to beneficial use, by 

placing the CCR on the land with no containment or other method of preventing environmental 

exposures, the facility is engaging in an activity that clearly falls within the statutory definition 

of disposal. See 42 U.S.C. § 6903(3)(“placing of solid waste...on any land, so that such solid 

waste...or any constituent thereof may enter the environment.”) Moreover, even where the 

facility intends the pile to be “temporary,” some amount of CCR inevitably remains in place. 

And even were this not the case, under section 1008(a)(3), EPA is authorized to establish criteria 

governing all aspects of solid waste management--which explicitly is defined to include 
Document submitted to conclude E.O.12866 Review

193

“storage” as well as all of the other activities identified by the commenters--to ensure the 

protection of human health and the environment. See 42 U.S.C. § 6903(28). 

Nevertheless, EPA agrees that not every activity that involves the management of CCR 

must occur in a unit that meets all of the technical requirements of a CCR landfill (e.g., 

groundwater monitoring). The key concern EPA is seeking to address with the inclusion of piles 

is the uncontrolled exposure from the extended, repeated, or indefinite placement of large 

amounts of unconsolidated CCR directly on the land. To the extent those exposures are 

controlled, whether through the use of tanks or some other kind of containment measures, the 

practice is neither considered to be a “pile” nor disposal in a landfill. 

To clarify this, and in response to the concern that the term “piles” was too vague, EPA 

has adopted a definition of the term “CCR pile” to identify those “piles” that are subject to the 

disposal requirements in this regulation. The final regulation specifies that a CCR pile means 

any non-containerized accumulation of solid, non-flowing CCR that is placed on the land. This 

definition mirrors the existing definition of “waste pile or pile” from the part 257 regulations, 

(i.e., the regulations that currently apply to CCR facilities), as well as the definition in part 260. 

The use of the phrase “non-containerized” is not intended to require that all activities occur 

within tanks or containment structures, but merely that concrete measures have been adopted to 

control exposures to human health and the environment. This could include placement of the 

CCR on an impervious base such as asphalt, concrete, or a geomembrane; leachate and run-off 

collection; and walls or wind barriers. To further clarify how this relates to EPA’s overall 

approach to beneficial use it is important to distinguish between CCR that is actually being used 

beneficially and CCR that may someday be used beneficially. CCR that is currently being used 

beneficially, for example, fly ash that has been transferred to a cement manufacturer and that is 
Document submitted to conclude E.O.12866 Review

194

stored off-site in a “temporary pile” that complies with all of the criteria in the definition to be 

considered a beneficial use including the fourth criterion relating to the placement of large 

quantities of unconsolidated CCR on the land, would not be subject to the regulations applicable 

to CCR disposal. Accordingly, the final regulation specifies that practices that meet the 

definition of beneficial use of CCR are not subject to the ‘disposal” requirements of the rule. 

By contrast, CCR located on-site that may someday be used beneficially but is not yet 

beneficially used remains subject to the disposal rule. Given that landfills and surface 

impoundments can be periodically dredged to provide material for beneficial use, any other 

approach would be impracticable, and would exclude from regulation many of the greatest 

sources of risk. An example of a “pile” that is not yet beneficially used is unconsolidated CCR 

placed on the land, that have been designated by the CCR facility to be transferred to another 

location for subsequent beneficial use (e.g., use as road bed) in the near future.

Several commenters also suggested that the definition of a CCR landfill should explicitly 

exclude the use of CCR at surface coal mining and reclamation operations, to reflect the 

Agency’s intention not to cover such activities. The Agency agrees and has revised the definition 

to explicitly provide that the term CCR landfill does not include the use of CCR at coal mining 

and reclamation operations. 

Consequently, the Agency is finalizing a definition of “CCR landfill or landfill” that can 

be found in § 257.73. On a related matter, the definition of CCR landfill or landfill contains the 

terms “sand and gravel pits or quarries.” EPA proposed a “sand and gravel pit and/or quarry” to 

mean an excavation for the commercial extraction of aggregate for use in construction projects. 

The Agency received comments on the definition of sand and gravel pit and/or quarry suggesting 

that the term “commercial extraction” was too narrow. Specifically commenters were concerned 
Document submitted to conclude E.O.12866 Review

195

it would exclude non-commercial extraction, such as gravel pits operated by municipalities, and 

exclude metallic mineral mines, nonmetallic mining for other than sand and gravel, and coal 

mines. EPA agrees that the use of the term “commercial extraction” renders the proposed 

definition too narrow, as there is no basis for distinguishing between commercial and noncommercial extraction, either because of the risks these activities pose, or any other 

consideration relevant to this rulemaking. EPA is, therefore, revising “sand and gravel pit and/or 

quarry” to mean an excavation for the extraction of aggregate, minerals, or metals. The term 

sand and gravel pit and/or quarry does not include subsurface or surface coal mines.

2. Definition of CCR surface impoundment

EPA proposed to define a “CCR surface impoundment” to mean a facility or part of a 

facility which is a natural topographic depression, man-made excavation, or diked area formed 

primarily of earthen materials (although it may be lined with man-made materials) which is 

designed to hold an accumulation of CCR containing free liquids, and which is not an injection 

well. Examples of CCR surface impoundments are holding, storage, settling, and aeration pits, 

ponds and lagoons. CCR surface impoundments are used to receive CCR that have been sluiced 

(flushed or mixed with water to facilitate movement), or wastes from wet air pollution control 

devices, often in addition to other solid wastes. 

The Agency received many comments on the proposed definition of CCR surface 

impoundment. The majority of commenters argued that the definition was overly broad and 

would inappropriately capture surface impoundments that are not designed to hold an 

accumulation of CCR. Commenters were concerned that the proposed definition could be 

interpreted to include downstream secondary and tertiary surface impoundments, such as 
Document submitted to conclude E.O.12866 Review

196

polishing, cooling, wastewater and holding ponds that receive only de minimis amounts of CCR. 

Commenters reasoned that these types of units in no practical or technical sense could be 

described as units “used to receive CCR that has been sluiced.” 

Other commenters raised concern that the definition did not differentiate between 

temporary and permanent surface impoundments. Commenters stated that many facilities rely 

on short-term processing and storage before moving CCR off-site for beneficial use or 

permanent disposal and that these units should not be required to comply with all of the technical 

criteria required for more permanent disposal impoundments. 

Upon further evaluation and review of the comments, the Agency has amended the 

definition of CCR surface impoundment to clarify the types of units that are covered by the rule. 

After reviewing the comments, EPA reviewed the risk assessment and the damage cases to 

determine the characteristics of the surface impoundments that are the source of the risks the rule 

seeks to address. Specifically, these are units that contain a large amount of CCR managed with 

water, under a hydraulic head that promotes the rapid leaching of contaminants. These risks do 

not differ materially according to the management activity (i.e., whether it was “treatment,” 

“storage” or “disposal”) that occurred in the unit, or whether the facility someday intended to 

divert the CCR to beneficial use. However, EPA agrees with commenters that units containing 

only truly “de minimis” levels of CCR are unlikely to present the significant risks this rule is 

intended to address. 

EPA has therefore revised the definition to provide that a CCR surface impoundment as 

defined in this rule must meet three criteria: (1) the unit is a natural topographic depression, manmade excavation or diked area; (2) the unit is designed to hold an accumulation of CCR and 

liquid; and (3) the unit treats, stores or disposes of CCR. These criteria correspond to the units 
Document submitted to conclude E.O.12866 Review

197

that are the source of the significant risks covered by this rule, and are consistent with the 

proposed rule. EPA agrees with commenters that relying solely on the criterion from the 

proposed rule that the unit be designed to accumulate CCR could inadvertently capture units that 

present significantly lower risks, such as process water or cooling water ponds, because, 

although they will accumulate any trace amounts of CCR that are present, they will not contain 

the significant quantities that give rise to the risks modeled in EPA’s assessment. By contrast, 

units that are designed to hold an accumulation of CCR and in which treatment, storage, or 

disposal occurs will contain substantial amounts of CCR and consequently are a potentially 

significant source of contaminants. However, EPA disagrees that impoundments used for “shortterm processing and storage” should not be required to comply with all of the technical criteria 

applicable to CCR surface impoundments. By “short-term,” the commenters mean that some 

portion of the CCR is removed from the unit; however, in EPA’s experience these units are never 

completely dredged free of CCR. But however much is present at any given time, over the 

lifetime of these “temporary” units, large quantities of CCR impounded with water under a 

hydraulic head will be managed for extended periods of time. This gives rise to the conditions 

that both promote the leaching of contaminants from the CCR and are responsible for the static 

and dynamic loadings that create the potential for structural instability. These units therefore 

pose the same risks of releases due to structural instability and of leachate contaminating ground 

or surface water as the units in which CCR are “permanently” disposed. 

The final definition makes extremely clear the impoundments that are covered by the 

rule, so an owner or operator will be able to easily discern whether a particular unit is a CCR 

surface impoundment. CCR surface impoundments do not include units generally referred to as 

cooling water ponds, process water ponds, wastewater treatment ponds, storm water holding 
Document submitted to conclude E.O.12866 Review

198

ponds, or aeration ponds. These units are not designed to hold an accumulation of CCR, and in 

fact, do not generally contain significant amounts of CCR. Treatment, storage, or disposal of 

accumulated CCR also does not occur in these units. Conversely, a constructed primary settling 

pond that receives sluiced CCR directly from the electric utility would meet the definition of a 

CCR surface impoundment because it meets all three criteria of the definition: it is a man-made 

excavation and it is designed to hold an accumulation of CCR (i.e., directly sluiced CCR). It 

also engages in the treatment of CCR through its settling operation. The CCR may be 

subsequently dredged for disposal or beneficial use elsewhere, or it may be permanently 

disposed within the unit. Similarly, secondary or tertiary impoundments that receive wet CCR or 

liquid with significant amounts of CCR from a preceding impoundment (i.e., from a primary 

impoundment in the case of a secondary impoundment, or from a secondary impoundment in the 

case of a tertiary impoundment), even if they are ultimately dredged for land disposal elsewhere 

are also considered CCR surface impoundments and are covered by the rule. To illustrate 

further, consider a diked area in which wet CCR is accumulated for future transport to a CCR 

landfill or beneficial use. The unit is accumulating CCR, while allowing for the evaporation or 

removal of liquid (no free liquids) to facilitate transport to a CCR landfill or for beneficial use. In 

this instance, the unit again meets all three definition criteria, it is a diked area (i.e., there is an 

embankment), it is accumulating CCR for ultimate disposal or beneficial use; and it is removing 

any free liquids, (i.e., treatment). As such, this unit would meet the definition of CCR surface 

impoundment. In all of these examples significant quantities of CCR are impounded with water 

under a hydraulic head that will be managed for extended periods of time. This gives rise to the 

conditions that both promote the leaching of contaminants from the CCR and are responsible for 

the static and dynamic loadings that create the potential for structural instability. These units 
Document submitted to conclude E.O.12866 Review

199

therefore all pose the same risks of releases due to structural instability and of leachate 

contaminating ground or surface water. 

3. Definition of Existing CCR Landfill

EPA proposed to define an “existing CCR landfill” to mean a CCR landfill which was in 

operation on, or for which construction commenced prior to [the effective date of the rule]. The 

proposed definition specified that a CCR landfill has commenced construction if the owner or 

operator has obtained the federal, state, and local approvals or permits necessary to begin 

physical construction; and either: (1) a continuous on-site, physical construction program has 

begun; or (2) the owner or operator has entered into contractual obligations – which cannot be 

cancelled or modified without substantial loss – for physical construction of the CCR landfill to 

be completed within a reasonable time.

In response to the proposed definition, the Agency received several comments arguing 

that the use of the phrase "was in operation on, or for which construction commenced prior to" 

would lead to confusion. Commenters contended that most units defined as CCR landfills at 

some point in time "were in operation" and had "commenced construction" prior to the effective 

date of the regulation. Commenters claimed that this definition would unnecessarily capture 

thousands of closed structural fill projects, including residential properties, commercial 

properties used by small businesses, and many recreational facilities. Furthermore, commenters 

doubted that EPA intended for the rule to cover all of these units and urged the Agency to clarify 

that closed units are excluded from the definition of existing CCR landfill.

Other commenters argued that the proposed definition of “existing CCR landfill“ should 

be modified to include lateral expansions of operation units where such an expansion is within 

the site footprint of an area already approved and permitted by the state for the landfill. 
Document submitted to conclude E.O.12866 Review

200

Commenters contended that while the proposed definition included undeveloped areas within the 

footprint of an approved permitted site, it also required that the construction be initiated at the 

site or that some type of binding contractual obligation be present. Commenters contended that 

the existence of a contractual obligation unfairly subjects undeveloped, yet approved permitted 

areas to design and operating standards for new CCR landfills based merely on the existence of a 

contract to commence construction. Commenters argued that such a distinction was arbitrary 

and capricious and provided no practical benefit. Other commenters questioned the usefulness of 

requiring a contractual obligation at all. As written, the commenters argued, that the definition 

was vague, unenforceable, and thus, not protective of human health and the environment. 

Commenters reasoned that there was no definitive or generally accepted meaning for the term 

“substantial loss” or the term “reasonable time” and an owner or operator, sensing that these 

proposed rules may be passed, could sign a contract now with minimum predetermined 

cancellation or modification penalties and a contract term of say five years or even longer to 

avoid the new unit requirements, i.e., a composite liner.

The commenters are correct that EPA did not intend to cover inactive landfills under this 

rule. The Agency agrees that, as drafted, the proposed definition could cause confusion. EPA 

therefore deleted the phrase “was in operation on the effective date of the rule” and has 

substituted the phrase “that receives CCR both before and after [the effective date of the rule].” 

EPA also agrees that the phrase "commenced construction prior to the effective date of the rule” 

could similarly cause confusion. Therefore, the Agency has made a similar revision, by adding 

the phrase “and receives CCR on or after [the effective date of the rule]” after the phrase “for 

which construction commenced prior to [the effective date of the rule].” These revisions will 

clarify which units are covered by the technical requirement of the rule and alleviate any 
Document submitted to conclude E.O.12866 Review

201

confusion. EPA is also making conforming modifications to the definition of “existing CCR 

surface impoundment.”

EPA disagrees that lateral expansions should be considered to be “existing” based solely 

on the fact that such an expansion is within the site footprint of an area already approved and 

permitted by the state. EPA has frequently distinguished between the types of requirements 

applicable to new and existing units, reasoning that in many instances, risk mitigation measures 

would be adequate such that existing units need not wholly retrofit to meet the new “state of the 

art.” For new units, however, the balance is generally struck in favor of requiring a greater 

degree of risk prevention, rather than relying solely on risk mitigation measures. In determining 

whether a unit is “new” or “existing,” EPA has historically considered that the equities lie in 

favor of considering a unit to be “existing” when there has been an irretrievable commitment of 

resources on the part of the facility. That has not occurred merely because permits have been 

obtained. While admittedly resources have been committed, at this stage modifications to the 

design and construction of the unit are still feasible. Specifically, the critical differences between 

the requirements applicable to new and existing CCR landfills are the type of liner that must be 

installed and the location restrictions that apply. Compliance with these requirements can be 

addressed through modifications to the design and construction of the unit, and are therefore 

readily feasible until construction has begun. 

EPA agrees with those commenters who were concerned that the phrase, “the owner or 

operator has entered into contractual obligations – which cannot be cancelled or modified 

without substantial loss – for physical construction of the CCR landfill to be completed within a 

reasonable time,” is vague and potentially subject to abuse. While this phrase has been included 

in other EPA regulations, those regulations operate within a regulatory program overseen by a 
Document submitted to conclude E.O.12866 Review

202

regulatory authority. No similar guarantee exists under these regulations. EPA could not 

discover a definitive or generally accepted meaning for the terms “substantial loss” or 

“reasonable time,” or develop sufficiently objective and determinate criteria for these concepts. 

Consequently, the Agency has decided to remove this provision from the definition of “existing 

CCR landfill.” EPA is retaining the two most important elements of the definition that will 

effectively determine whether the facility has irretrievably committed resources such that it 

would not reasonable to require compliance with all of the requirements applicable to new units. 

Accordingly, a unit will be considered to be existing if, first, the owner or operator has obtained 

the federal, state, and local approvals or permits necessary to begin physical construction; and 

second, that a continuous on-site, physical construction program has begun (i.e., groundbreaking 

has occurred). Therefore, EPA is finalizing the definition of “existing CCR landfill” that can be 

found in § 257.53.

4. Definition of Existing CCR Surface Impoundment”

EPA proposed to define an “existing CCR surface impoundment” to mean a surface 

impoundment which was in operation on, or for which construction commenced prior to [the 

effective date of the rule]. The proposal also specified that a CCR surface impoundment has 

commenced construction if the owner or operator has obtained the federal, state, and local 

approvals or permits necessary to begin physical construction; and either: (1) a continuous onsite, physical construction program has begun; or (2) the owner or operator has entered into 

contractual obligations – which cannot be cancelled or modified without substantial loss – for 

physical construction of the CCR landfill to be completed within a reasonable time.

EPA received many of the same comments on the definition of an existing CCR surface 

impoundment that were received on an existing CCR landfill. This included comments 
Document submitted to conclude E.O.12866 Review

203

requesting clarification that the term did not include impoundments that had ceased receiving 

CCR before the effective date of the rule. Commenters also suggested that EPA modify the 

definition to include the phrase that the surface impoundment “was in operation and had not yet 

ceased receiving CCR prior to the effective date of the rule” to make clear that the definition did 

not encompass units that are no longer receiving CCR on the effective date of the rule, even 

though the unit may not have completed final closure prior to the rule’s effective date. 

Commenters reasoned that units no longer receiving CCR on the effective date of the rule are not 

“in operation” and therefore should not be subject to the standards applicable to active units. 

Commenters also requested that EPA clarify that the definition of “existing CCR surface 

impoundment’ include units that were in operation on the effective date of the rule and that 

periodically dredged out during the operating life of the impoundment. Commenters contended 

that while this may seem self-evident, EPA needed to clarify that these impoundments would not 

be characterized as “new CCR surface impoundments.” 

The Agency is generally conforming the definition of an existing CCR surface 

impoundment to the revised definition of an existing CCR landfill. Although inactive CCR 

surface impoundments are covered by the final rule (unlike inactive CCR landfills), EPA decided 

it would provide greater clarity to establish a section specific to inactive CCR surface 

impoundments rather than merely including such units within the definition of an existing CCR 

surface impoundment. As discussed in greater detail in Unit XX, under § 257.100, any CCR 

surface impoundment that continues to impound CCR and water after the effective date of the 

rule, must either (1) breach, dewater, and place a cover on the unit within three years or (2) must 

comply with all of the requirements applicable to existing CCR surface impoundments. Without 
Document submitted to conclude E.O.12866 Review

204

the need to account for inactive CCR surface impoundments within the definition, the definitions 

of “existing” landfills and surface impoundments should be the same.

Thus, the Agency has removed the term “in operation” from the definition and has 

instead focused on when the surface impoundment received or will receive CCR. EPA has also 

deleted the provision that would have allowed a unit to be considered to be “existing” based on 

the existence of a contract. Accordingly, for purposes of this rule, a CCR surface impoundment 

will be considered to be “existing” if the unit received CCR both before and after the effective 

date of the rule. For example, if a CCR surface impoundment received CCR prior to the effective 

date and was in the process of dredging on the effective date with the intent of receiving 

additional CCR after the effective date, the unit would still be considered to be an “existing” 

rather than a new unit. Conversely, if a unit received CCR prior to the effective date and was no 

longer receiving CCR, this unit would be considered “inactive,” and would only be subject to the 

technical criteria applicable to “existing” CCR surface impoundments if they had not completed 

closure within three years. Similarly, if a CCR surface impoundment had commenced 

construction prior to the effective date with the intention of receiving CCR on or after the 

effective date of the rule, the unit would be considered an “existing” unit only if the physical 

construction program had begun (e.g., groundbreaking had occurred) with the appropriate 

federal, state and local approvals or permits in place. But if prior to the effective date of the rule, 

the permits had been obtained but the physical construction of the unit had not begun (e.g., 

groundbreaking had not occurred), the unit would be considered “new” and would be subject to 

all the applicable technical criteria for new CCR surface impoundments. Therefore, the Agency 

is finalizing the definition of “existing CCR surface impoundment” that can be found in § 257.53.

C. Location Restrictions and Individual Location Requirements 
Document submitted to conclude E.O.12866 Review

205

In the proposed rule, EPA stated that any RCRA subtitle D regulation would need to ensure that 

CCR landfills, CCR surface impoundments and all lateral expansions were appropriately sited to ensure 

that no reasonable probability of adverse effects on health or the environment from the disposal of CCR 

would occur. Under the subtitle D option, EPA proposed location restrictions for CCR units which 

included requirements relating to the placement of CCR in five general locations: (1) above the natural 

water table; (2) wetlands; (3) fault areas; (4) seismic impact zones; and (5) unstable areas. The proposed 

requirements relied in large measure, on the record EPA developed to support the 40 CFR part 258 

requirements for MSWLFs and on EPA’s Guide for Industrial Waste Management (EPA530-R-03-001, 

February 2003). EPA also chose to add one additional location restriction that would ban the placement of 

CCR units within two feet of the upper limit of the natural water table. This proposed requirement was 

originally included in the proposed rule, Standards for the Management of Cement Kiln Dust (64 FR 

45631, August 20, 1999) because of the potential damage to groundwater caused by the management of 

cement kiln dust at sites located below the natural water table. While the proposed cement kiln dust rule 

has not yet been finalized, EPA extended this reasoning to CCR by applying the same location restriction 

to CCR units. The proposed applicability of these location requirements varied depending on 

whether the unit was an existing or new CCR landfill, an existing or new CCR surface 

impoundment, or a lateral expansion of such units. For example, for existing CCR landfills, the 

Agency proposed that only the location requirement for unstable areas would apply. By contrast, 

the proposed rule applied all of the location restrictions to new CCR landfills and all CCR 

surface impoundments, both existing and new−an approach consistent with RCRA subtitle C and 

Congressional distinctions between the risks presented by landfills and surface impoundments. 

(See 75 FR 35198-35199.) This meant that owners or operators would need to close existing 

CCR surface impoundments located less than two feet above the natural water table, or for 

existing CCR units in sensitive but not prohibited locations, make a technical demonstration that 
Document submitted to conclude E.O.12866 Review

206

the unit met the requirements of a performance standard that serves as the alternative to the 

location restriction, retrofit the unit so that it could meet the performance standard, or close. For 

those CCR units that need to close (i.e., owners or operators that could not make the necessary

technical demonstrations), EPA proposed that the unit must close within five years of the 

effective date of the rule. If closure could not occur within the five year timeframe, the Agency 

proposed allowing for a case-by-case extension for up to two more years if the facility 

demonstrated that there was no alternative disposal capacity and no immediate threat to health or 

the environment. 

EPA proposed not to impose all of the location requirements on existing CCR landfills 

based on the conclusion that CCR landfills pose less risk and are structurally less vulnerable than 

existing CCR surface impoundments. EPA also raised concern that a significant number of these 

CCR landfills could be located in areas subject to these requirements, (particularly wetlands),

which could cause disposal capacity shortfalls in certain regions of the U.S., if existing CCR 

landfills in these locations were required to close. Disposal capacity shortfalls can pose

significant environmental and public health concerns based on the potential for significant 

disruption of solid waste management state-wide from the closure of these units. EPA concluded 

that these risks would be greater than the potential risks from allowing existing CCR landfills to 

remain in these locations, given that these units would be subject to all of the design and 

operating requirements of the rule. To ensure the accuracy of its preliminary conclusions, the 

Agency requested commenters to provide any available information regarding the number of 

existing CCR landfills located in these sensitive areas. The Agency also sought information 

regarding the extent to which CCR landfill capacity would be affected by applying all of the 

location restrictions to existing CCR landfills, the extent to which facilities could comply with 
Document submitted to conclude E.O.12866 Review

207

the proposed performance standards, and the costs that would be incurred to retrofit existing 

CCR landfills to meet these standards.

The Agency received numerous comments in response to the Agency’s request for 

additional information regarding the extent to which landfill capacity would be affected by 

applying all the proposed subtitle D location restrictions to existing CCR landfills. Commenters 

generally agreed with the Agency that applying the other location restrictions to existing CCR 

landfills would cause a significant decrease in disposal capacity across the country, although they 

did not provide any data or information which would support this concern. Commenters noted, 

however, that if existing CCR landfills located in these areas were to close, it would greatly 

complicate operations at many utilities. Affected facilities would need to find additional disposal 

capacity, which would require utilities to procure new real estate on which to site a new CCR 

landfill (which may be a significant distance from a power plant), obtain a new disposal permit 

for the CCR landfill (which can take an extended period of time), and potentially transport 

significant volumes of CCR great distances to newly-permitted facilities. Commenters argued 

that there was simply no environmental basis for causing this level of disruption to utility CCR 

disposal practices. 

EPA received no data or information in response to the Agency’s request for the costs 

associated with retrofitting a CCR surface impoundment or CCR landfill to meet the 

demonstrations for existing units. Similarly, the Agency received little to no information in 

response to EPA’s request for additional information on the location of these facilities. Some 

commenters acknowledged that specific states were located in some of these restricted areas but 

did not provide specific information on specific units.
Document submitted to conclude E.O.12866 Review

208

Overwhelmingly, the issue receiving the most comment was EPA’s intention to subject 

existing CCR surface impoundments to all of the new location criteria. Commenters contended 

that subjecting existing units to all of the location criteria was a radical departure from the 

location restriction provisions of the existing MSWLF rules on which the subtitle D option is 

based (i.e., existing MSWLFs are only subject to the floodplains and unstable areas restrictions) 

without any justification for regulating CCR surface impoundments more stringently than 

existing CCR landfills. Commenters argued that EPA must demonstrate that there are increased 

risks posed by each CCR surface impoundments based on its location; otherwise, they claimed,

there was no justification for EPA to subject CCR surface impoundments to more stringent 

location restrictions. Some commenters suggested that a more reasonable approach would be to 

limit the restrictions for existing CCR surface impoundments to unstable areas, consistent with 

the approach proposed for existing CCR landfills. Finally, commenters raised concern about the 

inconsistency between the preamble language and the corresponding regulatory text. 

Specifically, the preamble stated EPA’s intention to apply all of the location criteria to all CCR 

surface impoundments (existing and new) while the proposed regulatory language applied all 

location criteria only to new CCR surface impoundments and lateral expansions.

1. Applicability of the Location Criteria to Existing CCR Surface Impoundments 

EPA acknowledges the discrepancies between the preamble language and the regulatory 

text regarding the proposed regulatory language for the location restrictions as it applies to 

existing CCR surface impoundments. In the proposed rule, the regulatory language should have 

included, “all surface impoundments” as opposed to only “new surface impoundments.” 

EPA disagrees that in order to justify national minimum standards applicable to existing 

CCR surface impoundments, the Agency must demonstrate an adverse impact to human health 
Document submitted to conclude E.O.12866 Review

209

and the environment from each individual unit, based on the specific risks posed at each location. 

As an initial matter, it is well established that an agency may regulate a class of similarly situated 

entities through rulemaking, rather than on the basis of an individualized assessment of every 

entity that will be subject to the rule. And indeed, Congress specifically directed EPA to proceed 

by rulemaking to establish minimum national standards under RCRA sections 1008(a) and 

4004(a). Moreover, section 4004(a) does not require a demonstration of actual impacts, merely 

that these units present an unacceptable risk of harm. Thus, it is sufficient for EPA to establish a 

factual record demonstrating that the specific location restrictions in the final rule are necessary 

for CCR disposal units (landfills and surface impoundments), as a class, to ensure that there will 

be no reasonable probability of adverse effects on health or the environment. As discussed in 

greater detail in the next section and in Unit XI of the preamble, the factual record supports the 

need for all of the location standards for existing CCR surface impoundments imposed by this 

rule.

The Agency also rejects the suggestion that EPA establish the same location restrictions 

for both existing CCR landfills and CCR surface impoundments. As laid out in the proposal and 

elsewhere in this final rule in greater detail, the risks associated with CCR surface impoundments 

are substantially higher than the risks associated with CCR landfills, by approximately an order 

of magnitude. Surface impoundments are utilized by 45 percent of coal-fired power plants and in 

2000 accounted for disposal of one-third of all CCR generated.

46 Unlike landfills, CCR surface 

impoundments contain slurried residuals that remain in contact with ponded waters until closure. 

In a statewide investigation of impacts to groundwater quality from CCR disposal sites, the 

 

46 Rowe, C.L., Hopkins, W.A., Congdon, J.D., 2002. Ecotoxicological Implications of Aquatic Disposal 

of Coal Combustion Residues in the United States: A Review. Environmental Monitoring and 

Assessment, Vol. 80, pp. 207–276.
Document submitted to conclude E.O.12866 Review

210

Wisconsin Department of Natural Resources reported that closed sites which originally 

contained sluiced coal-combustion residuals displayed extremely elevated mean arsenic levels 

(as high as 364 μg/l)47. The highest contaminant concentrations in the study were associated 

with sluiced CCR residuals. 

In addition, releases of toxic contaminants to surface water and groundwater from mostly 

unlined CCR surface impoundments and ponds are a relevant factor in 34 of 40 cases of proven

damage to the environment (as well as in several cases of “potential” damage to the 

environment) from mismanagement of CCR.48 In many of these cases, effluent discharges from 

the surface impoundments caused significant ecological damage to aquatic life in nearby streams 

and wetlands. In one case, in 2002, the structural stability of a CCR surface impoundment was 

directly compromised by sinkhole development, leading to the release of 2.25 million gallons of

CCR. In another, an unusually weak foundation of ash and silt beneath a CCR surface 

impoundment (i.e., man-made unstable ground) was identified as one of several likely factors 

contributing to the dike failure that in 2008 resulted in the largest CCR spill in United States 

history. 

Unlike RCRA subtitle C, subtitle D does not explicitly authorize EPA to establish 

different standards for existing and new units, and Congress specifically intended subtitle D to 

address the risks from existing, abandoned “open dumps.” In the proposed rule preamble, EPA 

explained the rationale for applying these provisions to existing CCR surface impoundments, and 

 

47 Zillmer, M. and Fauble, P., 2004. Groundwater Impacts from Coal Combustion Ash Disposal Sites in 

Wisconsin. Waste & Materials Management, Wisconsin Department of Natural Resources, PUB-WA 

1174 2004. 

48 Cases of damage attributable to disposal of coal combustion residuals are summarized in Appendix I of 

the Proposed Rule, 40 CFR 35230-35239, June 21, 2010, and can be found in the RCRA Docket.
Document submitted to conclude E.O.12866 Review

211

the commenters have submitted nothing to rebut that rationale. Thus, EPA maintains its 

determination that application of the location standards to existing CCR surface impoundments is 

necessary to achieve the standard in section 4004(a). Absent these location restrictions, the risk 

of impacts to human health and the environment from releases from CCR units, including from 

the rapid and catastrophic destruction of CCR surface impoundments, sited in these sensitive 

areas would exceed acceptable levels. Given that the risks associated with CCR surface 

impoundments are substantially higher than the risks posed by CCR landfills, this is the 

appropriate regulatory course for existing CCR surface impoundments. 

In this rule, EPA is finalizing location restrictions that will ensure that CCR units are 

appropriately sited, that the structure of the CCR unit will not be adversely impacted by 

conditions at the site, and that overall there will be “no reasonable probability of harm to human 

health or the environment” due to the location of the CCR unit. EPA is finalizing different sets of 

location restrictions depending on whether the unit is a CCR landfill or CCR surface 

impoundment and whether it is an existing or new unit. Lateral expansions fall within the 

definitions of new units and are treated accordingly. These standards provide minimum national 

siting and performance criteria for all CCR units. The location restrictions under § 257.60 

through § 257.64 include: (1) placement above the uppermost aquifer; (2) wetlands; (3) fault 

areas; (4) seismic impact zones; and (5) unstable areas. Each of these locations is generally 

recognized as having the potential to impact the structure of any disposal unit negatively and as 

such, increase the risks to human health or the environment through structural failures or 

leaching of contaminants into the groundwater. Under the final rule and as proposed, new CCR 

landfills, existing and new CCR surface impoundments, and all lateral expansions will be 

required to comply with all of the location restrictions. Existing CCR landfills however, will be 
Document submitted to conclude E.O.12866 Review

212

subject to only two of the location restrictions – floodplains, and unstable areas. As noted in the 

proposed rule, and restated here, existing landfills and surface impoundments are already subject 

to the location standards in subpart A of 40 CFR 257 for floodplains, endangered species and 

surface waters. The final rule does not change this requirement, and so facilities should already 

be in compliance. The Agency is finalizing, as proposed, the unstable area location restriction for 

existing CCR landfills because the record clearly shows that failure of CCR units in these areas 

(e.g., due to instabilities in Karst terrains) have and in all likelihood would continue, in the 

absence of the restrictions in the final rule, to result in damage caused by the release of CCR 

constituents, affecting both groundwater and surface waters. As the Agency stated in the 

proposed rule, the impacts resulting from the failure of CCR units from location instability are of 

far more concern than any disposal capacity concerns resulting from the closure of existing CCR 

units in unstable areas. 

Conversely, and also consistent with the proposed rule, EPA is not applying the 

following location restrictions to existing CCR landfills: the requirement to construct a unit with 

a base located no less than 1.52 meters (five feet) above the upper limit of the uppermost aquifer, 

as well as the siting restrictions applicable to wetlands, fault areas, and seismic impact areas. 

Existing CCR landfills pose lower risks and are structurally less vulnerable than existing CCR 

surface impoundments. In addition, disposal capacity shortfalls, which could result if existing 

CCR landfills in these locations were required to close, raise greater environmental and public 

health concerns than the potential failure of the CCR landfills in these locales. 

2. Placement Above the Uppermost Aquifer. 

Under § 257.60(a) EPA is requiring new CCR landfills, existing and new CCR surface 

impoundments and all lateral expansions to be constructed with a base that is located no less than 
Document submitted to conclude E.O.12866 Review

213

1.52 meters (five feet) above the uppermost aquifer, or to demonstrate that there will not be an 

intermittent, recurring, or sustained hydraulic connection between any portion of the base of the 

CCR unit and the uppermost aquifer due to normal fluctuations in groundwater elevations 

(including groundwater elevations during the wet season). Existing surface impoundments that 

fail to achieve this location criteria standard must close. New CCR landfills, new CCR surface 

impoundments and all lateral expansions of existing and new CCR landfills and CCR surface 

impoundments cannot be constructed unless they meet one of these two standards. . In response 

to comment, the Agency has modified the criteria in two ways. First, EPA has replaced “a base 

that is located a minimum of two feet above the upper limit of the natural water table” with “a 

base no less than 1.52 meters (five feet) above the uppermost aquifer.” EPA received comment 

explaining that fluctuations in groundwater levels in many geological settings can exceed ten feet 

over the course of the year, and alleging that the proposed two foot minimum buffer between the 

base of the unit and the top of the water table would therefore be insufficiently protective. The 

commenter recommended that the minimum vertical separation be at least three to five feet from 

the base of the liner components. After additional research, EPA is finalizing a minimum buffer 

of five feet instead of two feet. EPA’s research confirmed the commenter’s claims. In addition, 

EPA determined that several states consider five feet between the base of the surface 

impoundment and the top of the uppermost aquifer to be the minimum distance that is protective 

of human health and the environment. These are California, Michigan, Nebraska, New York, 

West Virginia, and Wisconsin. The Agency has concluded from geographic and climatic 

spacing of these states that the hydrogeologic conditions within them encompass the range of 

conditions found in the United States. Therefore, EPA is finalizing a minimum buffer of five 

feet instead of two feet. 
Document submitted to conclude E.O.12866 Review

214

EPA is also clarifying the definition of the natural water table. As some commenters 

noted, there are many factors (hydrologic and geologic settings, nearby pumping, etc.) that 

influence the location of the groundwater table making it difficult to determine the “natural” 

level. In addition, as noted, local site-specific hydrogeologic conditions within the aquifer may 

cause the natural groundwater table to exceed five feet and vary as much as ten feet. To account 

for the possibility of such large seasonal fluctuations, EPA is revising the definition of 

“uppermost aquifer” to specify that the measurement of the upper limit of the aquifer must be 

made at a point nearest to the natural ground surface to which the aquifer rises during the wet 

season. This definition of “uppermost aquifer” will encompass large seasonal variations, and is a 

more appropriate parameter than “seasonal high ground water table” as suggested by several 

commenters and the proposed “natural water table” because it is more clearly defined. 

In § 257.60(a) the term uppermost aquifer has the same definition as under the general 

provisions of § 257.40: the geologic formation nearest the natural ground surface that is an 

aquifer, as well as lower aquifers that are hydraulically interconnected with this aquifer within 

the facility’s property boundary. This definition includes a shallow, deep, perched, confined or 

unconfined aquifer, provided it yields usable water. Although EPA originally proposed that all 

CCR surface impoundments be located ‘....above the upper limit of the natural water table’, the 

Agency is amending this requirement and replacing ‘water table’ with ‘uppermost aquifer’ to 

make it consistent with the way natural underground water sources are described elsewhere in 

the rule. 

EPA made a second revision to the criteria that were originally proposed. As an 

alternative to requiring that the CCR units described in this section be constructed with a base 
Document submitted to conclude E.O.12866 Review

215

that is located no less than five feet above the uppermost aquifer, owners and operators may 

instead demonstrate that there will not be an intermittent, recurring, or sustained hydraulic 

connection between any portion of the base of the CCR unit and the uppermost aquifer due to 

normal fluctuations in groundwater elevations (including groundwater elevations during the wet 

season).

This alternative standard was developed in response to concerns from commenters that a 

single depth to the aquifer failed to account for the wide variations in the level of water table 

fluctuations in different regions of the country. For example, arid regions of the country, such as 

Arizona, under normal conditions generally do not experience the same degree of fluctuations in 

groundwater elevations as more temperate regions, such as Minnesota. Accordingly, EPA 

developed an alternative performance standard focused on the conditions identified in the 

damage cases and the risk assessment that this location criterion was designed to prevent: 

specifically, where groundwater elevation is high enough to intersect the base of the waste 

management unit. In such situations, this hydraulic connection can enhance the transport of 

contaminant of concern from the CCR unit into groundwater. By requiring owners and operators 

to ensure that these conditions do not occur, the alternative standard to allow owners and 

operators to account for situations where there are relatively small variations in groundwater 

levels and a buffer of five feet is not necessary. This will also ensure that a CCR unit need not 

address situations where an infrequent, unexpected event (e.g., hurricane) could cause a brief, 

temporary condition where the uppermost aquifer rises to less than the prescribed five feet but 

which would not in and of itself constitute a long-term threat to the aquifer. However, where

normal fluctuations in groundwater elevation (including, but not limited to, seasonal or temporal 
Document submitted to conclude E.O.12866 Review

216

variations, groundwater withdrawal, mounding effects,49 etc.) will result in the failure of the unit 

to meet performance standard (i.e., no intermittent, recurring, or sustained hydraulic connection 

between the base of the CCR unit and the uppermost aquifer), the unit must close. 

In some recent damage cases, placement of large volumes of CCR into highly permeable 

strata in the disposal area promoted CCR-water interactions. For example, from 1995 to 2006 in 

Anne Arundel County, Maryland 4.6 million tons of CCR were placed directly in two sand and 

gravel quarries without a geomembrane liner or leachate collection system. Rainwater 

infiltration into exposed CCR coupled with groundwater-CCR interactions and the transmissivity 

characteristics of local strata contributed to rapid migration of heavy metals, including antimony, 

arsenic, cadmium, nickel, and thallium to residential drinking water wells located near the mine 

pits and significant deterioration of water quality as a result of placement of CCR. Similarly, 

from 1980 to 1997 in Lansing, Michigan, around 0.5 million tons of coal ash was dumped for 

disposal into a gravel pit with an elevated water table. A remedial investigation has established 

that groundwater mounding has immersed the CCR into the upper aquifer resulting in on-site 

exceedances of groundwater quality protection standards for sulfate, manganese, lead, selenium, 

lithium, and boron. Placement of CCR into un-engineered, unlined units in permeable strata has 

plainly led to adverse impacts to groundwater.

The phrase “normal fluctuations” has been used to clarify that EPA does not intend for 

the facility to account for extraordinary or highly aberrant conditions (e.g., one-in-a million or 

“freak” events). Normal fluctuation can include those resulting from natural as well as 

 

49 A phenomenon usually created by the recharge of groundwater from a manmade structure, such as a 

surface impoundment, into a permeable geologic material, resulting in outward and upward expansion of 

the free water table. Mounding can alter groundwater flow rates and direction; however, the effects are 

usually localized and may be temporary, depending upon the frequency and duration of the surface 

recharge events.
Document submitted to conclude E.O.12866 Review

217

anthropogenic sources. Natural sources that could affect groundwater levels include, but are not 

limited to precipitation, runoff, and high river levels. Anthropogenic sources that could affect 

groundwater levels include groundwater withdrawal, pumping, well(s) abandonment, and 

groundwater mounding. In satisfying this location restriction, it may be necessary for a 

professional engineer to model these effects before he can make the necessary certifications.50

EPA also notes that this modeling may include the same considerations already evaluated under 

some state programs.51

EPA expects that owners and operators will have sufficient information to determine 

whether their CCR unit meets either performance standard. Most, if not all, of this information 

would be information a facility would typically have as part of normal operations (e.g., the depth 

of the CCR unit itself), or that will be developed as part of implementing other rule requirements. 

For example, by relying on part of the groundwater monitoring system required under §§257.90-

257.98, the facility can obtain water level measurements in a sufficient number of locations (e.g., 

monitoring wells, piezometers) to use in determining whether they satisfy either performance 

standard. Similarly, under §257.91 a thorough characterization of the geology and 

hydrogeology of the site must be conducted. Finally, EPA notes that available technology and 

guidance are available for using existing groundwater monitoring wells, like those required 

under this final rule, to measure groundwater levels.52

 

50 For example, evaluations can be done to estimate groundwater mounding such as 

pubs.usgs.gov/sir/2010/5102/, www.groundwatersoftware.com/calculator_9_hantush_mounding.htm, and 

www.ndwrcdp.org/documents/wu-ht-02-45/wuht0245_electronic.pdf

51 See, e.g., dnr.wi.gov/topic/stormwater/standards/gw_mounding.html

52 See, e.g., U.S. EPA (Environmental Protection Agency). 2013. Groundwater Level and Well Depth 

Measurement. SESDPROC-105-R2. Region 4. Athens, GA. Available online at: 

www.epa.gov/region4/sesd/fbqstp/Groundwater-Level-Measurement.pdf
Document submitted to conclude E.O.12866 Review

218

3. Wetlands

In § 257.61 of this rule, EPA is finalizing the regulatory text essentially as proposed. 

Specifically, EPA is adopting a prohibition on locating all CCR surface impoundments and new 

CCR landfills, as well as lateral expansions of existing CCR units, in wetlands as defined in 40 

CFR 232.2, absent specific demonstrations made by the owner or operator that ensure the CCR 

unit will not degrade sensitive wetland ecosystems. These provisions place the burden of proof 

for these demonstrations directly on the owner or operator (the discharger). The owner or 

operator must make the results of these demonstrations available in the facility record. Failure to 

make any of the demonstrations will bar siting of the CCR unit in a wetland. 

In 2003, disposal of CCR in natural or man-made aquatic basins accounted for nearly 

one-third of all CCR land disposal. Historically, aquatic disposal of CCR has been attractive 

economically to facilities because of its lower overall cost relative to dry management and the 

ease of handling of residuals. During aquatic disposal, CCR is commonly piped as a slurried 

mixture to surface impoundments designed to retain the solids in contact with water for the life 

of the unit. Particulate solids from the waste stream gravitationally settle while clarified waters 

ultimately discharge into nearby streams and wetlands. 

The term ‘wetlands’ refers to those areas inundated or saturated by surface or 

groundwater at a frequency and over a duration sufficient to support a prevalence of vegetation 

typically adapted for life in saturated soil conditions. Wetlands include marshes, swamps, bogs 

and similar areas that are commonly located between open water and dry land. Under the CWA 

wetlands are considered ’special aquatic sites’ deserving of special protection because of their 
Document submitted to conclude E.O.12866 Review

219

ecologic significance. Wetlands are very important, fragile ecosystems that must be protected, 

and EPA has long identified wetlands protection as a high priority. 

Undisturbed, natural wetlands provide many benefits to society by improving water 

quality, providing essential breeding, rearing, and feeding grounds for fish and wildlife, reducing 

shoreline erosion, and absorbing flooding waters and pollution. Wetlands are also commercial 

source areas of products for human use such as timber, fish, and shellfish. Recreational hunters 

harvest wetland-dependent waterfowl. Wetland environments, however, may be adversely 

impacted by releases of wastes from co-located industrial facilities. Wetland ecosystems can be 

degraded by accidental discharges that can change the habitat value for fish and wildlife by 

obstructing surface water circulation patterns, altering substrate elevation, dewatering, or 

permanent flooding. 

In support of the provisions finalized in this rule, EPA is citing several damage cases, 

including 30 cases of “proven” damage to the environment that involve aquatic disposal of CCR, 

14 of which involve impacts to wetlands from release of CCR. For example, at the Hyco 

Reservoir in Roxboro, North Carolina from 1966 to 1990 the lake received contaminated effluent 

from coal ash disposal basins that were authorized by National Pollutant Discharge Elimination 

System (NPDES) permits under the CWA. High levels of the trace element selenium 

bioaccumulated in aquatic food chains (phytoplankton), poisoning invertebrates and fish in the 

lake, particularly species of sport fish (bluegill, largemouth bass), causing reproductive failure 

and severe declines in fish populations in the late 1970’s and early 1980’s. Consequently, from 

1988-2001 the North Carolina Department of Health and Human Services (NCDHHS) issued a 

consumption restriction advisory for selenium contamination in fish from the Reservoir. In 1990, 

a dry ash handling system was implemented resulting in lower selenium discharge and reduced 
Document submitted to conclude E.O.12866 Review

220

mean selenium concentration in reservoir waters. As of 2005, concentrations of selenium in fish 

tissues remained above a toxic threshold even with reduced influx of selenium, due to migration 

of the element from contaminated sediments to benthic food chains. The total monetized value of 

damage can be divided among ecologic factors (e.g., major impacts on fish), recreational factors 

(e.g., fishing trips not taken), depreciated real estate values, aesthetic factors, and human health 

damages (e.g., losses due to stress and anxiety from knowing ecosystem is poisoned) and is 

estimated at $877 million.53

Although this consideration is not relevant for purposes of establishing the minimum 

national criteria under RCRA sections 1008(a) and 4004(a), the rulemaking record demonstrates 

that the monetary cost of environmental damage from releases of coal combustion residuals at 

surface impoundments could be considerable. A report on the environmental damage caused by 

releases of CCR at 22 sites estimates the total cost of poisoned fish and wildlife at the surface 

impoundment sites at $2.32 billion. At twelve of these sites the releases were legally permitted 

under the CWA. Five of the 22 cases were caused by structural failures, two resulted from an 

unpermitted discharge, and one was from a landfill.

54

 Effluent contaminated with coal 

combustion residues is directly linked with high loadings of toxic metals in the discharge areas 

of aquatic basins, where some metals (primarily arsenic, cadmium, chromium, copper, lead, and 

selenium) have accumulated in aquatic food chains.

55

 In a research overview (literature 

synthesis) on the environmental effects of disposal of CCR, Rowe et al. (2002) listed adverse 

biological responses, including histopathological, behavioral, and physiological (reproductive, 

 

53 Lemly, A.D. 2010. Op.cit.

54 Lemly, A.D.2010. Op. cit.

55 Rowe, C.L. et. al. 2002. Op. cit.
Document submitted to conclude E.O.12866 Review

221

energetic, and endocrinological) effects, that have been observed in some vertebrates and 

invertebrates following exposure to and bioaccumulation of CCR-related contaminants.

Under the criteria finalized in this rule, in order to locate a CCR disposal unit or lateral 

expansion in a wetland, the owner or operator must: (1) successfully rebut the presumption that 

an alternative site (i.e., one that does not involve a wetland) is reasonably available for the CCR 

unit or lateral expansion; (2) show that the construction or operation of the unit will not cause or 

contribute to violations of any applicable State water quality standard, violate any applicable 

toxic effluent standard or prohibition, jeopardize the continued existence of endangered or 

threatened species or critical habitats, or violate any requirement for protection of a marine 

sanctuary; (3) show that the CCR unit or lateral expansion will not cause or contribute to 

significant degradation of wetlands; and (4) demonstrate that steps have been taken to attempt to 

achieve no net loss of wetlands.

In addition to these requirements, other federal laws may be applicable in siting a CCR 

disposal unit in a wetland. These include: Sections 401, 402, and 404 of the CWA; the Rivers 

and Harbors Act of 1989; the National Environmental Policy Act; the Migratory Bird 

Conservation Act; the Fish and Wildlife Coordination Act; the Coastal Zone Management Act; 

the Wild and Scenic Rivers Act; and the National Historic Preservation Act. In addition, the use 

of a wetlands location for a CCR unit may require a permit from the U.S. Army Corps of 

Engineers. To the extent these are applicable, compliance with these RCRA criteria does not 

alleviate the need to comply with these other federal requirements, and the owner or operator of 

the facility remains responsible for ensuring compliance with all applicable federal and state 

requirements. 
Document submitted to conclude E.O.12866 Review

222

The rule adopts a regulatory presumption that a less damaging alternative to locating a 

disposal unit in a wetland exists, unless the permit applicant can demonstrate otherwise. Thus, 

when proposing to locate a new facility or lateral expansion in a wetland, owners and operators 

must be able to demonstrate that alternative sites are not available and that the impact to 

wetlands is unavoidable. If this presumption is not clearly rebutted, then the CCR unit may not 

be sited in a wetland location. Such an analysis necessarily includes a review of reasonable 

alternatives to locating or laterally expanding CCR units in wetlands. As part of the evaluation of 

reasonable (that is, available and feasible) alternatives the owner or operator must show, and an 

independent professional engineer must verify, that operation or construction of the CCR 

disposal unit will not: (1) violate any applicable state water quality standards; (2) cause or 

contribute to the violation of any applicable toxic effluent standard or prohibition; (3) cause or 

contribute to violation of any requirement for the protection of a marine sanctuary; and 

jeopardize the continued existence of endangered or threatened species or critical habitats. 

When evaluating the impacts of a CCR unit on a wetland, the owner or operator must 

ensure that the unit cannot cause or contribute to significant wetland degradation. Therefore, the 

owner or operator and the qualified professional engineer must: (1) verify the integrity of the 

CCR unit, and its ability to protect ecological resources by addressing the erosion, stability, and 

migration potential of native wetland soils, and dredged and fill materials used to support the 

unit; (2) verify that the design and operation of the CCR unit minimizes impacts on fish, wildlife, 

and other aquatic resources and their habitat(s) from any release of coal combustion residue; (3) 

evaluate the effects of catastrophic release of CCR to the wetland and the resulting impacts on 

the environment; and (4) verify that ecological resources in the wetland are sufficiently 
Document submitted to conclude E.O.12866 Review

223

protected, including consideration of the volume and chemistry of the CCR managed in the unit; 

and any additional factors, as necessary.

When a wetland functions properly, it provides water quality protection, fish and wildlife 

habitat, natural floodwater storage, and reduction in the erosive potential of surface water. A 

degraded wetland is less able to effectively perform these functions. For this reason, wetland 

degradation is as big a problem as outright wetland loss, though often more difficult to identify 

and quantify. Any change in hydrology can significantly alter the soil chemistry and plant and 

animal communities. The common hydrologic alterations that can lead to significant degradation

in wetland areas include: (1) deposition of fill material, including CCR; (2) drainage for 

development; (3) dredging and stream channelization for development; (4) diking and damming 

to form ponds or impoundments; (5) diversion of CCR-bearing waters or other flows to or from 

wetlands; (6) addition of impervious surfaces in the watershed, thereby increasing water and 

CCR-bearing runoff into wetlands. These activities can mobilize CCR-bearing sediment; and 

once the sediment is discharged into the environment, toxic metals in CCR can become available 

to organisms within the wetland. Consequently, while the mere presence of one or more of these 

activities does not necessarily demonstrate that the CCR unit causes or contributes to significant 

degradation, the fact that they may do so means these activities need to be carefully evaluated. 

In determining what constitutes “significant” degradation, it is important to understand 

that although wetlands are capable of absorbing pollutants from the surface water, there is a limit 

to their capacity to do so. For the purposes of this rule, the primary pollutants of concern are 

CCR-bearing sediment and toxic metals. Although the risk assessment did not assess the 

exposure and hazard to wetlands, these can originate from uncontrolled runoff from the facility, 

fugitive dust from uncovered CCR landfills and piles, and uncontrolled discharge from CCR 
Document submitted to conclude E.O.12866 Review

224

disposal units (landfills, waste piles, surface impoundments). A clear example of biologically 

significant degradation in wetlands is when these toxic metals accumulate in benthic and aquatic 

food chains as a result of uncontrolled runoff. Another is obrution (smothering) of benthic 

organisms from discharge(s) of CCR to surface water, thereby jeopardizing the continued 

existence of organisms or critical habitats within the wetland. EPA notes that there are other 

requirements established under this rule that can also be relevant in this context, as they have the 

potential to reduce the likelihood that facility operations will cause or contribute to significant 

wetland degradation. EPA anticipates that as the facility begins to implement all of the 

requirements under this rule, the facility will consider how modifications to facility operations to 

address one requirement can affect compliance with other requirements. 

After consideration of these factors, if an existing CCR unit cannot meet all of the 

requirements in paragraphs (1)-(3) (i.e., if it causes or contributes to significant degradation, or if

no reasonable alternative to locating a new CCR disposal unit in wetlands is available), the 

facility can comply with the location criterion by compensatory steps must be taken to achieve 

no net loss of wetlands (as defined by acreage and function). Owners or operators must first take 

measure to avoid impacts to wetlands. If potential impacts cannot be avoided, all reasonable 

steps are to be taken to minimize such impacts to the extent feasible. Appropriate measures (for 

example, engineered containment systems to control discharge of leachate or surface water runoff to wetlands) will likely be site-specific and should be incorporated into the design and 

operation of the CCR disposal unit. Any remaining unavoidable impacts must be offset, or 

compensated for through all appropriate and feasible compensatory mitigation actions. This 

compensatory mitigation may take the form of restoration (re-establishment or rehabilitation of a 

wetland), establishment (creation of a man-made wetland where one did not previously exist) 
Document submitted to conclude E.O.12866 Review

225

enhancement (improving one or more wetland functions), and preservation (permanent 

protection of important wetlands through implementation of appropriate legal and physical 

mechanisms). The functions and values of a wetland will vary based on any number of site 

specific characteristics, including location, wetland type, hydrology, degradation, and whether it 

is natural or constructed to treat waste. Strictly limited to the application of the wetlands 

location requirements under this rule, any assessment of the nature and extent of mitigation 

required under the CCR rule shall consider these kinds of characteristics, including wetlands 

designed for treatment for CCR. The agency recognizes that the function and value of a 

particular man-made wetland constructed to perform a wastewater treatment function may 

present a unique situation that may affect both the determination of whether the wetland is 

significantly degraded, and the nature and extent of any required compensatory mitigation. This 

discussion refers only to the wetlands-related requirements of this rule and does not affect any 

requirements or obligations under the Federal Water Pollution Control Act (33 USC 1251, et 

seq.) and its implementing regulations.

Although EPA is not finalizing an outright ban on siting of existing or new CCR units in 

wetlands, the Agency continues to believe that discharges to wetlands of pollutants that can be 

reasonably avoided should be avoided. Therefore, the amount and quality of compensatory 

mitigation may not substitute for avoiding and minimizing impacts. For purposes of this rule, 

EPA assumes CCR units that are designed to avoid discharge of coal combustion residues into 

wetlands have less adverse impact to the aquatic environment than CCR units that ultimately 

discharge such residues in wetlands.

4. Fault Areas 
Document submitted to conclude E.O.12866 Review

226

In § 257.62 of this rule, EPA is banning the location of new CCR landfills, existing and 

new CCR surface impoundments, and all new lateral expansions within 60 meters (200 feet) of a 

fault that has had displacement in Holocene time, unless the owner or operator demonstrates that 

an alternative setback distance of less than 60 meters (200 feet) will prevent damage to the 

structural integrity of the unit. For existing surface impoundments, the demonstration is required 

only if the unit is located closer than 60 meters (200 feet) to an active Holocene fault. If a 

demonstration cannot be made, than the existing surface impoundment must close. These 

requirements have been adopted with only minor changes from the proposal, and will minimize 

the risks associated with CCR disposal units located in fault areas. 

Stresses produced during earthquake motion can cause serious damage to landfill 

integrity via seismically induced ground failure and associated rupture of liner systems and 

subsequent damage to leachate collection systems. Or if the unit is unlined, seismic motion could 

disrupt landfill caps and foundation soils that impede migration of percolating water. Potential 

damage to CCR disposal units resulting from structures located across a fault include surface 

breakage, cracks and fissures between fill and confining slopes, slope failure via landslides, 

liquefaction-induced lateral spreading and settlement of the pile, disruption of surface water and 

drainage control systems, and rupture of leachate collection systems. In impoundments, for 

example, interior dike failure and leakage, and rupture of multilayer liner systems would also be 

of concern. Failure of the leachate collection system may prevent removal of generated leachate, 

allowing it to pond on the liner. If the liner system is ruptured, this may create a pathway for 

leachate to migrate into and contaminate the uppermost aquifer. In addition to the potential 
Document submitted to conclude E.O.12866 Review

227

damage to leachate collection and liner systems, the integrity of the landfill slopes could also be 

impaired by fault rupture, potentially exposing coal combustion residuals to surface runoff.

The best protection is to avoid locating new CCR landfills and all CCR surface 

impoundments across faults and fault zones subject to displacement. For new units or lateral 

expansions there is no need to construct units in these areas. For existing surface impoundments, 

the Agency has been unable to find any way to retrofit or engineer the unit to be protective. A

setback distance of 60 meters (200 feet) from the outermost damage zone of a Holocene fault 

will provide an adequate margin of safety to protect the facility from displacements due to 

surface faulting and any associated damage because 60 meters typically covers the zone of 

deformation where the ground may be bent or warped as a consequence of fault movement. By 

including this as a siting requirement for new units the risk of rupture of the unit, including any 

liner and leachate collection systems, due to surface faulting will be minimized.

Observations of engineered landfill response during earthquake motion come primarily 

from California where field data have been reported from MSWLFs (including some meeting the 

current part 258 standards) affected by strong shaking from six major nearby earthquakes. In 

these large magnitude events (M ≥ 6.7), bedrock peak horizontal ground accelerations, an index 

of the intensity of earthquake motion, endured by the landfills were in excess of 0.3g. 

Engineered dry MSWLFs in California are reported to have performed well after strong 

earthquake motion (no documented incidence of an earthquake-induced release of contaminants 

harmful to human health or to the environment). Minor cracking of cover soils and breaking of 

vertical wells and headers were among the most common types of damage reported at MSWLFs

subject to strong ground shaking. In the 1994 Northridge earthquake, only one landfill compliant 

with RCRA Part 258 standards experienced tears in a liner (a geomembrane liquid barrier): one 
Document submitted to conclude E.O.12866 Review

228

tear 23 meters in length. However, there is little data on seismic stability and performance from 

industrial solid waste landfills with geosynthetic liners or units with water-saturated CCR waste. 

The Agency, therefore, remains concerned over the potential instability of engineered disposal 

units, and particularly CCR surface impoundments, under seismic loadings. Accordingly, EPA 

is prohibiting new CCR landfills, CCR surface impoundments, and any new extensions from 

sites located within an active fault zone, unless the owner or operator makes a demonstration, 

certified by a qualified professional engineer, that an alternative setback distance of less than 60 

meters will prevent damage to the structural integrity of the unit. 

EPA is clarifying its definition of fault to incorporate updated technical information.56 

Although a fault can be thought of as a simple planar surface across which there has been 

measurable displacement of one side relative to the other, field-based observations show fault 

architecture to often be complex. In the geologic literature faults developed in the upper crust are 

characterized as zones of brittle deformation composed of linked fault segments, with each 

segment composed of one or more subparallel, curved, or anastomosing fault cores nested within 

a damage zone. Some fault zones may contain broad deformational features such as pressure 

ridges and sags rather than clearly defined fault scarps or shear zones.57 Fault cores are regions 

of high strain slip that have accommodated most of the displacement and are marked by 

mylonites, cataclastites, and gouge, whereas the damage zone is characterized by low strain 

structures mechanically related to the growth of the fault zone such as small faults, fractures, 

veins and folds. To avoid displacement that would damage unit integrity, it is best to restrict new 

 

56 Sibson, R.H. 2003. Thickness of the Seismic Slip Zone. Bulletin of the Seismological Society of 

America, Vol. 93, No. 3, pp. 1169–1178

57 Bryant, W.A. and Hart, E.W., 2007. Fault-Rupture Zones in California. Special Publication 42 (Interim 

Revision), California Division of Mines and Geology, Sacramento, California.
Document submitted to conclude E.O.12866 Review

229

CCR landfills and surface impoundments, and all new extensions, to locations no less than 60 

meters from the outermost damage zone created by an active fault. Fault zones can range from 

one meter to several kilometers in width.

For purposes of this section, a fault is considered active if it has moved during Holocene 

time. Holocene time is defined as the geological epoch which began at the end of the 

Pleistocene, at 11,700 years BP, and continues to the present. In the field, evidence for Holocene 

activity may be hard to obtain. Therefore, the Agency cautions that faults which show no 

evidence for Holocene activity may not necessarily be inactive.

To investigate active faults, EPA expects owners and operators of CCR units to follow 

standard engineering and geologic practices. Technical considerations include: (1) a geologic 

reconnaissance of the site to determine the location of active faults. Such a reconnaissance would 

include utilizing the seismic analysis maps and tools (Quaternary fault maps, earthquake 

probability maps) of the United States Geological Survey (USGS) Earthquake Hazards Program 

(http://earthquake.usgs.gov/hazards/apps/); and (2) a site fault characterization within 1000 

meters of a site to determine whether it is within 60 meters of an active fault. Such 

characterizations would include subsurface exploration, including drilling or trenching, to locate 

any fault zones and evidence of faulting, trenching perpendicular to any faults or linements 

found within 60 meters of the site, and determination of the age of any displacements. Based on 

this information, the qualified professional engineer would prepare a report that delineates the 

location of any active (Holocene) fault, including any damage zones, and the associated 60 meter 

setback. To take advantage of an alternative setback distance of less than 60 meters, the owner or 

operator must make a demonstration, certified by a qualified professional engineer, that the CCR 

landfill, surface impoundment, or lateral expansion has a foundation or base capable of providing 
Document submitted to conclude E.O.12866 Review

230

support for the structure, and capable of withstanding hydraulic pressure gradients to prevent 

failure due to settlement, compression, or uplift, and all effects of ground motions resulting from 

at least the maximum surface acceleration expected from a probable earthquake.

5. Seismic Impact Zones

In § 257.63, EPA is adopting the provisions applicable to seismic impact zones, as 

proposed. The rule prohibits new CCR landfills, existing and new CCR surface impoundments 

and all lateral extensions from being located in seismic impact zones unless the owner or 

operator makes a demonstration, certified by an qualified professional engineer, that all 

containment structures, including liners, leachate collection systems, and surface water control 

systems, are designed to resist the maximum horizontal acceleration in lithified earth material 

from a probable earthquake. A Seismic impact zone means an area having a 2% or greater 

probability that the maximum expected horizontal acceleration, expressed as a percentage of the 

earth’s gravitational pull (g), will exceed 0.10 g in 50 years. Seismic zones, which represent 

areas of the United States with the greatest seismic risk, are mapped by the U.S. Geological 

Survey and readily available for all the U.S. (http://earthquake.usgs.gov/hazards/apps/). 

Maximum Horizontal Acceleration in lithified earth material means the maximum 

expected horizontal acceleration at the ground surface as depicted on a seismic hazard map, with 

a 98% or greater probability that the acceleration will not be exceeded in 50 years, or the 

maximum expected horizontal acceleration based on a site-specific seismic risk assessment. 

This requirement translates to a 10% probability of exceeding the maximum horizontal 

acceleration in 250 years. 

For units located in seismic impact zones, as part of any demonstration, owners and 

operators should include: (1) a determination of the expected peak ground acceleration from a 
Document submitted to conclude E.O.12866 Review

231

maximum strength earthquake that could occur in the area; (2) a determination of the sitespecific seismic hazards such as soil settlement; and (3) a facility design that is capable of 

withstanding the peak ground acceleration. Seismic designs broadly should include a response 

analysis to quantify the demands of earthquake motion on facility structures (landfills, surface 

impoundments, liners, covers, leachate collection systems, surface water handling systems), 

liquefaction analyses of both waste and foundation soils to evaluate stability under seismic 

loading, and a slope stability and deformation analyses. Design modifications to accommodate 

seismic risks should include use of conservative design factors, use of ductile materials, built-in 

redundancy for critical system components, and other measures capable of mitigating the 

potential for seismic upset.58

Following trends in earthquake engineering, seismic design criteria for new CCR 

landfills, new CCR surface impoundment and all lateral expansions should be based on a 

“withstand without discharge” standard.

59 EPA interprets the performance standard in this 

criterion (“designed to resist the maximum horizontal acceleration in lithified earth material from 

a probable earthquake”) to require any new CCR disposal unit located in a seismic impact zone 

to be designed to withstand seismic motion from a credible earthquake without damage to the 

foundation or to the structures that control leachate, surface drainage, or erosion. In other words, 

the CCR disposal unit must be able to withstand an expected earthquake without discharging 

 

58 The seismic location standard requires a demonstration that a CCR disposal unit can withstand the 

stresses imposed by peak ground acceleration during earthquake motion. The seismic factor of safety is a 

unitless measure of strength calculated for fill material assuming earthquake conditions. It is the ratio of 

material shear strength relative to the magnitude of shear forces acting on the material. For a CCR 

disposal unit, the seismic location demonstration could be composed of numerous factor of safety

calculations showing that the structural components of the unit have factors of safety greater than or equal 

to 1.00.

59 Kavazanjian, E., 1999. Seismic Design of Solid Waste Containment Facilities. Proceedings of the Eight 

Canadian Conference on Earthquake Engineering Vancouver, BC, pp. 51-89.
Document submitted to conclude E.O.12866 Review

232

waste or contaminants. The owner or operator must make a demonstration, certified by a 

qualified professional engineer, that the CCR unit has a foundation or base capable of providing 

support for the structure, and capable of withstanding hydraulic pressure gradients to prevent 

failure due to settlement, compression, or uplift and all effects of ground motions resulting from 

at least the maximum surface acceleration expected from a probable earthquake. In practice, the 

Agency recognizes that the CCR landfill or CCR surface impoundment may sustain some limited 

damage during an earthquake, but ultimately, the unit design must remain capable of preventing 

harmful release of coal combustion residuals, leachate, and contaminants both during and after 

the seismic event.

6. Unstable Areas 

EPA laid out its rationale for these requirements in the proposal at 75 FR 35201. No 

significant comments were received on either this rationale or the specific regulatory provisions. 

Consequently, EPA is adopting the regulatory text as proposed. Specifically, under § 257.64(a) 

new and existing CCR landfills, new and existing CCR surface impoundments and all lateral 

expansions are prohibited from sites classified as unstable areas unless the owner or operator 

makes a demonstration, certified by an qualified professional engineer, that engineering 

measures have been incorporated into the CCR unit's design to ensure that the structural 

components will not be disrupted. EPA considers a structural component to include any 

component used in the construction and operation of CCR landfill or CCR surface impoundment 

that is necessary to ensure the integrity of the unit and to ensure that the contents will not be 

released to the environment, including liners, leachate collection system, embankments, 

spillways, outlets, final covers, inflow design flood controls systems. Liners and leachate 

collection systems require a firm, secure foundation to maintain their integrity, and may be 
Document submitted to conclude E.O.12866 Review

233

disrupted as a result of uneven settlement induced by hydrocompaction. Similarly, sudden 

differential movement resulting from CCR placement and the consequent exceedance of the 

weight-bearing strength of subsurface materials in unstable areas can destroy liners and damage 

the unit’s structural integrity, resulting in catastrophic release of CCR. It is essential for the 

owner or operator of any CCR unit to extensively evaluate the adequacy of the subsurface 

foundation support for the structural components of the unit. Therefore, the Agency is making 

this demonstration mandatory for all CCR units; existing CCR units for which a demonstration 

cannot be made must be closed.

EPA has adopted the following definitions without material change from the proposal:

Unstable area means a location that is susceptible to natural or human-induced events or forces 

capable of impairing the integrity of some or all of the structural components responsible for 

preventing releases from a CCR unit. Natural unstable areas include those areas that have poor 

soils for foundations, areas susceptible to mass movements, and karst terrains. Structural 

components mean liners, leachate collection systems, final covers, run-on/run-off systems, and 

any other component used in the construction and operation of a CCR unit. Poor foundation 

conditions means those areas where features exist which may result in inadequate foundation 

support for the structural components of a CCR unit. Areas susceptible to mass movement means 

those areas of influence (i.e., areas characterized as having an active or substantial possibility of 

mass movement) where the movement of earth material at, beneath, or adjacent to the CCR unit, 

because of natural or man-induced events, results in the downslope transport of soil and rock 

material by means of gravitational influence. Areas of mass movement include, but are not 

limited to, landslides, avalanches, debris slides and flows, solifluction, block sliding, and rock 

fall. Karst terrain means an area where karst topography, with its characteristic erosional 
Document submitted to conclude E.O.12866 Review

234

surface and subterranean features, is developed as the result of dissolution of limestone, 

dolomite, or other soluble rock. Characteristic physiographic features present in karst terrains 

include, but are not limited to, dolines (sinkholes), vertical shafts, sinking streams, caves, seeps, 

large springs, and blind valleys. 

The owner or operator must consider at a minimum, the following factors when 

determining whether an area is unstable: (1) on-site or local soil conditions that may result in 

significant differential settling; (2) on-site or local geologic or geomorphologic features; and (3) 

on-site or local human-made features or events (both surface and subsurface). To evaluate 

subsurface conditions for purposes of § 257.64(c)(3), EPA considers it essential that the owner or 

operator conduct a geotechnical site investigation, certified by a qualified professional engineer, 

to identify any potential thick layers of soil that are soft and compressible (e.g., loess, 

unconsolidated clays, wetland soils), which could cause a significant amount of postconstruction differential settlement of foundation soils, adjacent embankments, and slopes unless 

improved. In addition, it is essential that the investigation identify on-site or local soil conditions 

that are conducive to downslope movement of soil, rock, and/or debris (alone or mixed with 

water) under the influence of gravity. Local topography, surface and subsurface soils, surface 

slope angles, surface drainage and runoff patterns, seepage patterns, rock mass orientations, joint 

patterns, fissures, and any other landscape factors that could influence downslope movement 

should be identified. Anthropogenic activities that could induce instability include mining, cut 

and fill activities during construction, excessive drawdown of groundwater, which may cause 

excessive settlement or bearing capacity failure of foundation soils, and use of an old landfill as 

the foundation for a new landfill without verification of complete settlement of the underlying 

wastes. 
Document submitted to conclude E.O.12866 Review

235

In designing a new CCR unit located in an unstable area, recognized and generally 

accepted good engineering practices dictate that a stability assessment should be conducted to 

prevent a destabilizing event from damaging the structural integrity of the component systems. 

For CCR units this involves three components: (1) an evaluation of subsurface conditions, (2) an 

analysis of slope stability, and (3) an examination of related design needs. In addition to 

explaining site constraints, identifying any soft soils, and recommending any appropriate ground 

improvement techniques, the assessment report should include a description of: the site, site 

geology; and investigative methodology; the results from all site investigations including 

subsurface exploration, field and laboratory tests, and test results; the subsurface profile, 

recommended foundation types, depths, and bearing capacities; the water content, grain-size 

distribution, shear strength, plasticity, and liquefaction potential of foundation soils and subsoils; 

and other foundation consolidation and settlement issues relevant to site development. 

In addition to assessing the ability of soils and rocks to serve as a foundation, it is 

essential that the report also include a stability assessment of excavated sideslopes, aboveground 

embankments or dikes, and retaining structures. The slope stability analyses are performed as 

part of an evaluation of the design configuration under all potential hydraulic and loading 

conditions, including conditions that may exist during construction of a lateral or vertical 

expansion. As part of any demonstration, owners and operators should make an assessment, 

certified by a qualified professional engineer, that finalized site embankments and slopes are able 

to maintain a stable condition. In addition to evaluating the potential for post-construction 

differential settlement, the stability assessment should also consider seepage-induced saturation 
Document submitted to conclude E.O.12866 Review

236

and softening of soils, particularly at CCR surface impoundments and CCR landfill sites that 

manage effluent.

Engineering considerations for CCR landfills and lateral expansions located in unstable 

areas are expected to be similar to those for MSWLFs, which can be found in EPA’s 1993 

Technical Manual on Solid Waste Disposal Facility Criteria (EPA530-R-93-017). For surface 

impoundments the relevant design criteria are found in the Agency’s 1991 Technical Resource 

Document on Design, Construction and Operation of Hazardous and Non-Hazardous Waste 

Surface Impoundments (EPA/530/SW-91/054). Any stability assessment should consider the 

following: (1) the adequacy of the subsurface exploration program; (2) the liquefaction potential 

of the embankment, slopes and foundation soils; (3) the expected behavior of the embankment 

slopes, and foundation soils when they are subjected to seismic activity; (4) the potential for 

seepage-induced failure; and (5) the potential for differential settlement.

For facilities in areas of karst, to support the demonstration required under the 

regulations, the owner or operator would need to evaluate the subsurface conditions to ensure 

that the unit is located away from the influence of potential sinkholes. For areas where the 

solution-weathered limestone is close to the surface (e.g., Florida) recognized and generally 

accepted good engineering practices dictate that there must be no conduits beneath the CCR unit 

that allow piping of groundwater into the karst aquifer, or shallow caves that could cause sudden 

collapse of the unit foundation. Where unconsolidated sediments cover underlying limestone, 

piping is commonly marked by paleosinks where sands and clays from the overburden have 

filled solution cavities in the underlying limestone.

60

 Local hydraulic gradients in paleosinks 

 

60 For examples, see Garlanger, J.E., Foundation Design in Florida Karst. Online presentation by 

Ardaman & Associates. http://www.ardaman.com/foundation_design.htm.
Document submitted to conclude E.O.12866 Review

237

typically point downward. EPA generally expects the potential for sinkhole development to be 

minimal at locations in karst areas where there are no paleosinks, or historical record of sinkhole 

development, and where there are no local hydraulic gradients that point downward. 

In making a demonstration, it is important for owners and operators of CCR landfills and 

surface impoundments in karst areas to adequately characterize subsurface conditions. Karst 

hydrogeology is complex, since contaminant flows can occur along paths and networks that are 

discreet and tortuous, and groundwater monitoring wells must be capable of detecting any 

contaminants released from the CCR unit into the karst aquifer. Therefore, the owner or operator 

will need to ensure, with verification by a qualified professional engineer, that monitoring wells 

installed in accordance with § 257.90 will intercept these pathways. Verification will usually 

necessitate the use of tracers to track groundwater flow towards offsite seeps or springs from the 

uppermost aquifer beneath the facility. 

Any engineered solution employed to mitigate weak ground strength in karst areas must 

be able to prevent the kind of foundation collapse and settlement that could lead to sudden 

release to the environment of CCR waste with its toxic constituents and associated leachate. 

Solution cavities present at the site should be filled with grout or other suitable stiff material to 

avoid further crumbling and erosion. Where necessary, CCR unit foundations could be 

reinforced with engineered ground supports such as concrete footings that bridge voids. Larger 

caverns could be filled with concrete to underpin the CCR unit foundation by transferring load to 

the cavern floor. However, such engineered solutions are complex and costly, and the best 

protection is not to site CCR landfills and surface impoundments in karst areas. Nevertheless, 

this rule does not ban the location of CCR landfills, surface impoundments, or lateral extensions 

in karst areas. 
Document submitted to conclude E.O.12866 Review

238

7. Closure of Existing CCR Landfills and Existing CCR Surface Impoundments

The final provisions of § 257.60 require owners or operators of an existing CCR surface 

impoundment to demonstrate that the unit meets the minimum requirements for placement above 

the uppermost aquifer (i.e., constructed with a base located no less than 1.52 meters (five feet) 

above the upper limit of the uppermost aquifer) no later than 42 months after the date of 

publication of this rule in the Federal Register. The Agency is setting the compliance date at 18 

months, or one year after the effective date of this rule, to allow owners and operators time to 

adequately study and characterize seasonal variations in the elevation of the top of the uppermost 

aquifer. Owners and operators must initiate closure of those units that fail to make this 

demonstration no later than six months from this determination, except in limited circumstances 

as discussed in Unit VI.H. 

Owners and operators of existing CCR surface impoundments subject to §§ 257.61 -

257.64 of this rule and existing CCR landfills subject to § 257.64, must complete demonstrations 

by the date corresponding to 42 months from publication of this rule. The Agency is setting the 

compliance deadline at 42 months, to allow owners and operators time to complete the requisite 

studies and to complete any engineering measures necessary to allow the CCR unit to meet the 

performance standards. If closure is warranted, it must be initiated no later than 48 months from 

publication of this rule. Closure and post-closure care must be done in accordance with §§ 

257.100 – 103; which allow certain regulatory flexibilities provided specific conditions are met. 

D. Design Criteria – Liner Design 

EPA proposed that existing CCR landfills without a composite liner could continue to receive 

CCR and continue without violating the open dumping prohibition. Conversely, EPA proposed 
Document submitted to conclude E.O.12866 Review

239

that existing CCR surface impoundments would be required to retrofit with a composite liner 

system, as defined in the proposed rule, within five years of the effective date of the rule or to 

close. EPA also proposed that all new CCR units must be constructed with a composite liner and 

leachate collection and removal system.

In the proposal, EPA defined a composite liner to mean a liner system consisting of two 

components; the upper component consisting of a minimum 30-mil flexible membrane liner 

(FML), and the lower component consisting of at least a two-foot layer of compacted soil with a 

hydraulic conductivity of no more than 1×10−7 cm/sec.61 FML components consisting of high 

density polyethylene (HDPE) were required to be at least 60-mil thick; and the FML component 

was required to be installed in direct and uniform contact with the compacted soil component. 

EPA also solicited comment on a number of issues, including: (1) whether EPA should 

allow facilities to use an alternative design for new CCR disposal units; (2) whether clay liners 

designed to meet a 1x10-7cm/sec hydraulic conductivity might perform differently in practice 

than modeled in the risk assessment, including a request for specific data on the hydraulic 

conductivity of clay liners associated with CCR disposal units; and (3) whether the effectiveness 

of such additives as organosilanes, would allow the use of these additives in lieu of composite 

liners. (See 75 FR 35203 and 35222.)62 With respect to the last two issues, the Agency received 

little comment. However, in response to the use of alternative liner designs in lieu of a 

composite liner (as defined in the rule), significant comment was received. Commenters 

advocated for a number of alternative composite liner designs, with a majority recommending 

 

61 The definition of hydraulic conductivity is being promulgated as proposed. Hydraulic conductivity

means the rate at which water can move through a permeable medium (i.e., the coefficient of 

permeability).

62 The terms compacted soil and compacted clay are used interchangeably, i.e., when referring to a 

compacted soil liner this is the same as referring to a compacted clay liner (CCL). 
Document submitted to conclude E.O.12866 Review

240

that a geosynthetic clay liner (GCL) be allowed as an alternative to the lower component of the 

composite liner. Other commenters stated that GCLs alone should be allowed as an alternative to 

the proposed composite liner. Still others argued that alternative liner designs, such as an 

FML/FML63 provided a level of performance similar to the proposed composite liner system and 

should be allowed. Conversely, there were also comments opposing the use of any alternative 

liners, claiming that alternatives have not been proven to be effective. 

EPA also received significant comment on the actual design of the composite liner 

system proposed by the Agency as it pertained to CCR surface impoundments (see 75 FR 35202-

35203). 64 Commenters argued that the proposed requirement for a leachate collection and 

removal system in a CCR surface impoundment was illogical since it would have to be 

constructed between the lower component (two feet of compacted soil) and upper component 

(flexible membrane liner) and the proposed rule specifically states that the flexible membrane 

liner component must be installed in direct and uniform contact with the compacted soil 

component. Commenters reasoned that the inclusion of a leachate collection and removal system 

between the upper and lower components precluded direct and uniform contact between the two 

components and that placing a leachate collection and removal system between the lower and 

 

63 Current terminology favors the use of geomembrane liner or GM when referring to flexible membrane 

liners or FMLs. Hereafter in the preamble, except when referring to specific comments or the proposed 

rule, and in the final rule, the Agency will use the term geomembrane liner or GM in place of flexible 

membrane liner or FML. 

64 See proposed § 257.71 which states that an existing CCR surface impoundment shall be constructed 

with a composite liner and a leachate collection system between the upper and lower components of the 

composite liner; where a composite liner means a system consisting of two components; the upper 

component consisting of a minimum 30-mil flexible membrane liner (FML) and a lower component 

consisting of at least a two-foot layer of compacted soil with a hydraulic conductivity of no more than 

1x10-7cm/sec. The FML component would be required to be installed in direct and uniform contact with 

the compacted soil component (see 75 FR 35243).
Document submitted to conclude E.O.12866 Review

241

upper components of a composite liner would compromise the integrity of the composite liner. 

With regard to this last point, the Agency has reviewed the requirements for a proposed 

composite liner system as it would pertain to CCR surface impoundments and agrees that the 

leachate collection and removal system requirements proposed for CCR surface impoundments 

would be counterproductive; EPA proposed this requirement in error. The integrity of the 

composite liner system is indeed dependent upon the direct and uniform contact of the upper GM 

component with the lower soil component. The proposed requirement for CCR surface 

impoundments to construct a leachate collection system between the FML and soil components 

would prevent the direct and uniform contact of the upper and lower components and, therefore, 

compromise the integrity of the composite liner. For this reason, EPA is not requiring a leachate 

collection and removal system for new surface impoundments or any lateral expansion of a CCR 

surface impoundment. 

While EPA agrees with those commenters arguing that new CCR disposal units should 

only be installed with a composite liner system of some kind, the Agency has concluded that not 

all alternative designs for a composite liner system should necessarily be rejected as 

insufficiently protective. Many commenters provided strong and compelling evidence that the 

specific composite liner system described in the proposed rule was not always feasible or 

necessary to protect groundwater resources and that alternate composite liner designs could be 

equally protective, and may be a necessity in many areas of the country where soil with the 

appropriate hydraulic conductivity may not be available (e.g., Alaska).65

 

65 See for example comments from the states of Alaska (EPA-HQ-RCRA-2009-0640-06409); Florida 

(EPA-HQ-RCRA-2009-0640-06846); and North Carolina (EPA-HQ-RCRA-2009-0640-09282) available 

at www.regulations.gov.
Document submitted to conclude E.O.12866 Review

242

In re-evaluating the proposed requirement for a composite liner system, EPA was 

influenced by a number of factors.66 First, the data provided by commenters showing the 

performance of a GM/GCL design. Second, EPA’s own studies showing that a GM/GCL liner 

can be constructed to achieve hydraulic efficiencies in the range of 99 to 99.9% which meets or 

exceeds the hydraulic performance of a GM/compacted clay liner (CCL) design. 67 In addition, 

these high efficiencies demonstrate that the GCL component of a GM/GCL composite liner is at 

least as effective in impeding leakage through holes in the GM component of the composite liner 

system as a CCL with a hydraulic conductivity no more than 1x10-7cm/sec.

68 In fact, EPA has 

developed guidance for the selection and installation of various types of liners including a 

GM/GCL.69 And third, EPA was influenced by the many comments arguing that a “one-size-fits 

all” approach to liner design stifles design innovation and regulatory flexibility in addressing site 

specific factors such as geologic or climatic conditions. These commenters reasoned that if EPA 

established some type of performance standard for composite liners, it would mitigate the 

negative impacts of a “one-size fits all” regulatory framework. 

1. Development of Composite Liner Design Criteria 

In this final rule EPA is requiring all new CCR units to be designed and constructed with 

 

66 Geomembranes (GMs), which are flexible membrane liners (FMLs), are thin materials manufactured 

from polymers and reinforced with woven fabric or fibers which are used as hydraulic barriers. Resins 

used to manufacture geomembrane liners typically include high density polyethylene (HDPE), linear low 

density polyethylene (LLDPE), low density linear polyethlene (LDLPE), very low density polyethylene 

(VLDPE) and polyvinyl chloride (PVC). Geomembranes manufactured using HDPE are the least flexible 

of the geomembranes.

67 USEPA, “Assessment and Recommendations for Improving the Performance of Waste Containment 

Systems,” EPA 600/R-02/029, December 2002. http://nepis.epa.gov/Adobe/PDF/P1001O83.pdf

68 USEPA, “Assessment and Recommendations for Improving the Performance of Waste Containment 

Systems,” EPA 600/R-02/029, December 2002. 

69 USEPA, “Guide for Industrial Waste Management,” Chapter 7 

(http://www.epa.gov/osw/nonhaz/industrial/guide/pdf/chap7b.pdf).
Document submitted to conclude E.O.12866 Review

243

a composite liner as specified in § 257.70. EPA is also providing the owner or operator with an 

option to install an alternative composite liner provided it meets the required performance 

standard and it is certified by a qualified professional engineer. EPA has concluded, consistent 

with many of the comments received and its own analysis, that an alternative composite liner for 

new CCR units is warranted if it can be shown to be equivalent to the performance of a 

composite liner and affords the same protections to groundwater resources as a composite liner. 

The Agency is promulgating this alternative option to provide flexibility in designing and 

constructing a protective composite liner system that addresses site specific conditions and 

situations. The Agency acknowledges that it was overly prescriptive by requiring one particular 

type of liner rather than relying on a performance standard to define the lower component of the 

composite liner. The overwhelming amount of data supporting the effectiveness of a GC/GCL 

liner has convinced the Agency that the final rule should allow for some flexibility in composite 

liner designs. As such, the Agency is allowing new CCR units to be designed and constructed 

with an alternative composite liner, as described below, provided the lower component of the 

composite liner meets a specified performance standard that ensures it functions in a manner 

equivalent to the composite liner system defined in the rule. 

Composite liner systems installed in either a CCR landfill or CCR surface impoundment 

provide an effective hydraulic barrier by combining the complementary properties of the two 

different liner components. The geomembrane provides a highly impermeable layer that can 

maximize leachate collection and removal in a CCR landfill or minimize infiltration of leachate 

in a CCR surface impoundment, while the soil component (e.g., CCL) serves as a backup in the 

event of any leakage/infiltration from the geomembrane occurs. Data indicate that alternatives to 

the lower component of the composite liner system (e.g., GCLs) are available and can perform at 
Document submitted to conclude E.O.12866 Review

244

a level equivalent to a compacted soil liner, based on a comparison of their flow rates with two 

feet of compacted soil with a hydraulic conductivity of no more than 1x10-7cm/sec. 

2. Liner Designs That Would Not Meet the Requirements of a Composite Liner or 

Alternative Liner

Contrary to the arguments made by several commenters, EPA has concluded that a 

composite liner consisting of two 30-mil GMs (GM/GM) will not provide an equivalent degree 

of protection as a composite liner consisting of a GM and two feet of compacted soil, or an 

alternative composite liner such as a GM/ GCL. While GMs have the advantages of extremely 

low rates of water permeation, the disadvantages of a composite liner consisting of two GMs 

include leakage through occasional GM imperfections and punctures, potential for slippage along 

the interface between the GMs, and GM embrittlement over time. Furthermore, a critical 

component of a composite liner is the compacted soil or GCL component beneath the GM layer 

that will impede the flow of liquid that may leak through a hole or defect in the GM. This added 

protection cannot be achieved using two GMs for the composite liner. Additionally, the potential 

exists for liquid transport through the GMs through holes caused by punctures, tears, flawed 

seams, etc. If a puncture occurs, the puncture could compromise both GMs and create a conduit 

for liquid flow to underlying permeable soil. Moreover, a liner system consisting of two GMs in 

contact with each other poses the risk of creating a slip plane that may compromise the stability 

of the disposal unit (although EPA acknowledges that using textured GMs would reduce or 

eliminate this particular risk). These data are documented in EPA research.

70

Consistent with the previous determination, EPA has also determined that the double 

liner system set forth in Florida regulations (see Florida Rules 62-701.400(3)(c),F.A.C) also does 

 

70 “Assessment and Recommendations for Improving the Performance of Waste Containment Systems.” 
Document submitted to conclude E.O.12866 Review

245

not meet the level of performance achieved by EPA’s composite liner system or the alternative 

liner system. While this double liner system provides the advantage of a leak detection system 

between the two GMLs, the lower composite liner, consisting of a 60-mil HDPE over six inches 

of soil with a saturated hydraulic conductivity of less than or equal to 1 x 10-5cm/sec, is not 

equivalent to a GM over two feet of compacted soil with a hydraulic conductivity of less than or 

equal to 1 x 10-7cm/sec. To be hydraulically equivalent, soil with a hydraulic conductivity of 1 x 

10-5cm/sec would need to be on the order of 100 times thicker than soil with a hydraulic 

conductivity of less than or equal to 1 × 10-7cm/sec. Similarly, a lower composite liner 

consisting of a 60-mil HDPE over a GCL with a hydraulic conductivity not greater than 1 x 10-7

cm/sec would require a GCL thickness of 24 inches to be equivalent to a GM over two feet of 

compacted soil with a hydraulic conductivity of less than or equal to 1 x 10-7cm/sec. 

EPA has also examined the performance of GCLs approved for use as alternatives to 

composite liners in MSWLFs.71 The EPA report titled “Assessment and Recommendations for 

Improving the Performance of Waste Containment Systems,”

72 concluded that if a CCL or GCL 

is used alone, liquid migration can occur over the entire area of the liner that is subject to a 

hydraulic head. The report also concluded that in a composite liner, leakage will only occur at 

the location of the geomembrane penetration (e.g., hole, tear), and will be much slower than flow 

through an orifice due to the hydraulic impedance provided by the CCL or GCL alone. The 

report also evaluated, among other characteristics, the hydraulic efficiencies of a GM/GCL 

 

71

 “Geosynthetic Clay Liners Used in Municipal Solid Waste Landfills,”

http://www.epa.gov/wastes/nonhaz/municipal/landfill/geosyn.pdf; “Geosynthetic Clay Liners in Waste 

Containment,” http://www.epa.gov/superfund/remedytech/tsp/download/2001_meet/prez/carson.pdf; and 

“Assessment and Recommendations for Improving the Performance of Waste Containment Systems,” 

http://www.epa.gov/nrmrl/pubs/600r02099/600r02099.htm

72

 “Assessment and Recommendations for Improving the Performance of Waste Containment Systems.” 
Document submitted to conclude E.O.12866 Review

246

composite liner system for 28 cells at seven landfills. Liner hydraulic efficiencies were reported 

between 97% and 100%. However, potential stability problems were reported with GCLs 

constructed on slopes greater than 10 H:1 V (5.7°), and GCLs may not be appropriate for the 

disposal of liquid wastes or sludges. The Agency is also concerned that GCLs, being much 

thinner than the two feet of compacted soil required for composite liners, may allow for the flow 

of liquids through the GCL at a faster rate than through two feet of compacted soil. Taking all of 

this information into account, the Agency remains unconvinced that a GCL alone is a viable 

alternative to a composite liner. 

3. Design Requirements 

a. Existing CCR Landfills

As proposed, the final rule allows existing CCR landfills as defined in § 257.54, to 

continue to operate without retrofitting with a composite liner and leachate collection and 

removal system. As previously discussed, given the volume of the material currently managed in 

CCR landfills, the potential for disruption in CCR disposal capacity if existing CCR landfills 

were required to retrofit would be significant. Significant disruptions in the state-wide solid 

waste management (and possibly power generation) are associated with significant risks to 

public health and the environment in their own right. EPA has concluded that these risks are 

greater than the risks associated with allowing unlined CCR landfills to continue to operate. 

Further, existing CCR landfills will be required to comply with the extensive groundwater 

monitoring and corrective action requirements, among others, to ensure that any groundwater 

releases from the CCR unit are identified and promptly remediated, which will significantly 

mitigate the risks from these existing units. By themselves, the risk assessment results and the 

risk migration from the other regulatory requirements in this rule would not support a decision to 
Document submitted to conclude E.O.12866 Review

247

allow these CCR units to continue to operate on a national basis. But when the risks associated 

with the level of disruption EPA estimates to be possible from requiring existing CCR landfills 

to retrofit are also included, the totality of the evidence supports a determination that allowing 

these units to continue operating meets the section 4004(a) standard. 

b. Existing CCR Surface Impoundments

In a departure from the proposed rule and after considerable evaluation and analysis, the 

Agency is finalizing a provision to allow all existing CCR surface impoundments to remain in 

operation provided certain conditions are met.73 Owners or operators of existing CCR surface 

impoundments are required, within one year of the effective date of the rule, to document, 

certified by a qualified professional engineer, whether the unit is constructed with any one of the 

three liner types: (1) a liner consisting of a minimum of two feet of compacted soil with a 

hydraulic conductivity of more than 1x10-7 cm/sec; (2) a composite liner that meets the 

requirements of § 257.70(b); or (3) an alternative liner that meets the requirements of § 

257.70(c). In some instances, owners or operators may have information readily available to 

determine if an existing CCR surface impoundment is constructed with one of the three liner 

types listed above. On the other hand, this information may not be readily available and may 

require an owner or operator to conduct an engineering evaluation to determine if the unit was 

constructed with any of the three liner type. Factors such as the availability of engineering 

personnel and weather may impede the engineering evaluation. Therefore, EPA believes that 12 

months from the effective date, or 18 months from publication of the rule, is a reasonable amount 

of time to make the determination whether the existing CCR surface impoundment was 

 

73 Existing CCR surface impoundments will not be required, as was proposed, to retrofit to a composite 

liner or close within five years of the effective date of the rule (see 57 FR 35202). 
Document submitted to conclude E.O.12866 Review

248

constructed with one of the three liner types described above. Existing surface impoundments 

with liners that meet the criteria established for any of the three specified liner types are 

considered to be an “existing lined CCR surface impoundments.” These existing lined surface 

impoundments can continue to operate until the owner or operator decides to initiate closure, 

provided the unit does not meet other requirements of the rule that independently mandate 

closure of the unit (.e.g., location criteria (§§ 257.60-257.64) or structural integrity factors of 

safety (§ 257.73)). Existing unlined CCR surface impoundments must also cease receiving CCR 

and initiate closure if an owner or operator determines, at any point in time, as part of its 

groundwater monitoring program that the concentrations of one or more constituents listed in 

Appendix IV to part 257 are detected at a statistically significant level above the groundwater 

protection standard established for that unit. EPA agrees with the many commenters who argued 

that existing unlined CCR surface impoundments should not be required to close prematurely if 

they are operating as designed and are complying with all of the requirements of the rule, 

including all groundwater protection standards. Taking into account the additional protections 

required under this rule (e.g., location restrictions, groundwater monitoring, corrective action, 

structural integrity criteria, inspections and fugitive dust controls), the Agency has concluded 

that the risks posed by unlined CCR surface impoundments that are not “leaking” (i.e., exceeding 

any groundwater protection standard) are not sufficient to warrant requiring these units to close. 

However, once a groundwater protection standard is exceeded (i.e., the unit is leaking), without 

any type of liner system in place, leachate will flow through the unit and into the environment 

unrestrained and the only corrective action strategy that EPA can determine will be effective at 

all sites nation-wide requires as its foundation the closure of the unit. 

EPA acknowledges that it may be possible at certain sites to engineer an alternative to 
Document submitted to conclude E.O.12866 Review

249

closure of the unit that would adequately control the source of the contamination and would 

otherwise protect human health and the environment. However, the efficacy of those engineering 

solutions will necessarily be determined by individual site conditions. As previously discussed, 

the regulatory structure under which this rule is issued effectively limits the Agency’s ability to 

develop the type of requirements that can be individually tailored to accommodate particular site 

conditions. Under sections 1008(a) and 4004(a), EPA must establish national criteria that will 

operate effectively in the absence of any guaranteed regulatory oversight (i.e., a permitting 

program), to achieve the statutory standard of “no reasonable probability of adverse effects on 

health or the environment” at all sites subject to the standards. EPA was unable to develop a 

performance standard that would allow for alternatives to closure, but would also be sufficiently 

objective and precise to minimize the potential for abuse. There are too many factors that 

determine whether a particular engineering solution will meet the section 4004(a) standard at a 

particular site. And the risks of these units are simply too high.

Conversely, existing lined surface impoundments that exceed their groundwater 

protection standard are in a better position to manage the leak because it is usually caused by 

some localized or specific defect in the liner system that can more readily be identified and 

corrected. Consequently, this rule is not requiring existing lined CCR surface impoundment to 

close if an exceedance of a groundwater protection standard is detected; rather the Agency is 

affording the owner or operator with the opportunity to rely on corrective action measures to 

bring the risks back to acceptable levels (i.e., control the source of the release and remediate the 

contamination), without mandating closure of the unit.

c. New CCR Landfills and New CCR Surface Impoundments and All Lateral Expansions

Both the CCR damage case history and the risk assessment clearly show the need for and 
Document submitted to conclude E.O.12866 Review

250

the effectiveness of appropriate liners in reducing the potential for groundwater contamination at 

CCR landfills and CCR surface impoundments. Accordingly, EPA is finalizing liner and leachate 

collection and removal system requirements for new CCR landfills and all lateral expansions of 

these units. Similarly, EPA is finalizing liner requirements for new CCR surface impoundments 

and all lateral expansions of these units.

Specifically, EPA is requiring new CCR landfills, new CCR surface impoundments, and 

all lateral expansions be constructed with a composite liner (see § 257.70). The composite liner 

must consist of two components; an upper component consisting of a minimum 30-mil

geomembrane liner (GM), and a lower component consisting of at least a two-foot layer of 

compacted soil with a hydraulic conductivity of no more than 1x10-7centimeters per second 

(cm/sec). GM components consisting of high density polyethylene (HDPE) must be at least 60-

mil thick and the GM or upper liner component must be installed in direct and uniform contact 

with the compacted soil or lower liner component 

New CCR landfills or lateral expansions of these units are also required to be constructed 

with a leachate collection and removal system designed to maintain less than a 30-centimeter 

depth of leachate over the composite liner. A leachate collection and removal system is not 

required for new CCR surface impoundments because, as previously discussed, a leachate 

collection system installed between a single composite liner system is not practicable and would 

compromise the integrity of the composite liner system. 

In addition, in response to comments on the proposed rule, EPA is allowing alternatives 

to the lower component of the composite liner system provided the flow rate through the lower 

component is no greater than the flow rate through two feet of compacted soil with a hydraulic 

conductivity of 1 x 10-7cm/sec. The lower component must also be a recognized liner material; 
Document submitted to conclude E.O.12866 Review

251

e.g., soil, clay, or GCL. Alternative composite liners using compacted soil or clay as the lower 

component must be constructed with the upper component in intimate contact with the lower 

component; i.e., the geomembrane must be installed to ensure good and uniform contact with the 

lower component. The hydraulic conductivity for the two feet of compacted soil used in the flow 

rate comparison must be no greater than 1 x 10-7cm/sec. The hydraulic conductivity of the lower 

component must be determined using recognized and generally accepted engineering methods, 

for example, ASTM D5084 - 10, “Standard Test Methods for Measurement of Hydraulic 

Conductivity of Saturated Porous Materials Using a Flexible Wall Permeameter,” ASTM 

International, West Conshohocken, PA, 2012, DOI: 10.1520/D5084-10, www.astm.org for 

compacted soils or clays, or ASTM Standard D6766 - 12, “Standard Test Method for Evaluation 

of Hydraulic Properties of Geosynthetic Clay Liners Permeated with Potentially Incompatible 

Aqueous Solutions,” ASTM International, West Conshohocken, PA, 2012, DOI: 

10.1520/D6766-12, www.astm.org for GCLs. The flow rate comparison for the lower 

component must be made using Darcy’s Law for gravity flow through porous media, which is an 

empirical law which states that the velocity of flow through porous medium is directly 

proportional to the hydraulic gradient. The use of Darcy’s Law to calculate fluid flow through 

porous media is a well-established and generally accepted engineering methodology, and is the 

foundation for EPA's Composite Model for Leachate Migration with Transformation Products

(EPACMTP) and is generally recognized to evaluate steady state flow of liquids through soils 

and GCLs.

74

 EPACMTP is a subsurface fate and transport model EPA uses to simulate the 

 

74 See for example EPA's Composite Model for Leachate Migration with Transformation Products 

(EPACMTP) at http://www.epa.gov/epawaste/nonhaz/industrial/tools/cmtp/, “Assessment and 

Recommendations for Improving the Performance of Waste Containment Systems.” 
Document submitted to conclude E.O.12866 Review

252

impact of the release of constituents present in waste that is managed in land disposal units. 

Accordingly, the flow rate comparison for the lower component of alternative composite liner 

must be made using the following equation which is derived from Darcy’s Law.

Q

A

= q = k (

h

t

+ 1)

where: Q = flow rate,

A = surface area of the liner,

q = flow rate per unit area,

k = hydraulic conductivity of the liner,

h = hydraulic head above the liner, and

t = thickness of the liner.

A qualified professional engineer must certify that the design and construction of either 

the composite liner or the alternative composite liner meets the requirements of §§ 257.70(b) or 

(c). 

EPA has also supplemented the composite liner criteria for landfills with performance 

standards that provide more precise direction to the professional engineer regarding the 

“recognized and generally accepted good engineering practices” that need to be used in the 

design and construction of composite liner systems to ensure that the liner system will continue 

to perform as designed. These criteria, which have been codified at §§ 257.70(b) and 257.70(c), 

have been adopted in response to comments requesting that EPA provide the professional 

 

Giroud, J.P., Badu-Tweneboah, K. and Soderman, K.L., 1997, “Comparison of Leachate Flow Through 

Compacted Clay Liners and Geosynthetic Clay Liners in Landfill Liner Systems,” Geosynthetics 

International, Vol. 4, Nos. 3-4, pp. 391-431 

(http://www.geosyntheticssociety.org/Resources/Archive/GI/src/V4I34/GI-V4-N3&4-Paper7.pdf), and 

"Design Considerations for Geosynthetic Clay Liners (GCLs) in Various Applications," Geosynthetic 

Research Institute, January 9, 2013 (http://www.geosynthetic-institute.org/grispecs/gcl5.pdf).
Document submitted to conclude E.O.12866 Review

253

engineers that will be required to certify that CCR units meet the requirements of the rule with 

more precise and objective criteria. These criteria reflect the engineering specifications necessary 

to prevent liner failures resulting from improper design and construction and to ensure that the 

liner will continue to perform correctly. These provisions will ensure not only that the liner is 

properly designed and constructed, but also that the system will continue to safely perform 

throughout the landfill’s active life and through post closure care. The criteria have been adopted 

from the technical provisions proposed under the subtitle C provisions for CCR landfills, and are 

consistent with design requirements set forth for hazardous waste landfills regulated under Part 

265 of RCRA, as well as existing guidance and recognized good engineering practices for the 

design and construction of MSWLFs.

75

 

Specifically, the Agency is modifying the composite and alternative liner design 

requirements by requiring the composite or alternative liner to be chemically compatible with the 

CCR and of adequate strength and thickness to prevent failure. The liner system must also 

provide appropriate shear strength between the two components to prevent sliding of the upper 

component. In addition, the Agency is requiring that liners be placed on an adequate foundation 

and installed to cover all areas that might come into contact with the CCR. 

For new CCR landfills, which are required to have a leachate collection and removal 

system designed and operated to maintain less than a 30 centimeter depth of leachate, the 

Agency is also requiring, that the leachate collection and removal system be constructed of 

sufficient strength and thickness to prevent collapse from the pressure of the CCR and to 

 

75

 “Technical Guidance Document: Quality Assurance and Quality Control for Waste Containment 

Systems.” U.S. Environmental Protection Agency. Risk Reduction Engineering Laboratory, Office of 

Research and Development, Cincinnati, OH 45268. EPA/600/R-93/182. September 1993.
Document submitted to conclude E.O.12866 Review

254

minimize clogging during the active life and post closure care period.76

4. Vertical Expansions of New and Existing CCR Landfills and All Lateral Expansions

In the proposed rule, EPA stated that CCR landfills could vertically expand without 

retrofitting, in order to alleviate concerns with regard to CCR disposal capacity in the short term. 

In the few comments to the proposed rule which mentioned vertical expansions of landfills,

commenters requested that the Agency clarify the design standards that vertical expansions 

would have to meet. Information collected to date, which is included in the docket supporting the 

final rule, leads the Agency to conclude there are no issues unique to vertical expansions of CCR 

landfills that warrant modifications to the technical standards being promulgated in this rule. 

Therefore, vertical expansions of existing CCR landfills are not subject to the provisions 

governing new units, but are subject to all applicable requirements for existing CCR landfills. To 

be clear however, while the location requirements relating to the placement above the water 

table, wetlands, fault areas, and seismic impact zones do not apply to existing CCR landfills, all 

of these restrictions apply to lateral expansions of existing CCR disposal units, as well as new 

CCR disposal units. Consequently, under this rule, owners or operators of existing CCR landfills 

can continue to vertically expand their existing facilities in these locations, but must comply with 

the provisions governing new units if they wish to laterally expand.

5. Construction of New CCR Landfills or any Lateral Expansion over an Existing CCR Unit

On August 2, 2013, EPA published a NODA that among other things, solicited comment 

regarding a particular type of CCR management unit described by some commenters in the 

 

76

 Hardin, PE, Christopher D, and Perotta, PE Nick L. “Operations and Maintenance Guidelines for Coal 

Ash Landfills – Coal Ash Landfill are NOT the Same as Subtitle D Solid Waste Landfills”. Presented at 

the 2011 World of Coal Ash Conference; May 9-12, 2011 in Denver, Colorado. 

http://www.flyash.info/2011/127-Hardin-2011.pdf
Document submitted to conclude E.O.12866 Review

255

proposed rule as “overfills” (see 78 FR 46940). Overfills are CCR landfills constructed over a 

closed CCR surface impoundment. As discussed in the NODA, in developing the proposed rule, 

EPA was not aware that CCR was managed in this fashion and so did not either evaluate this 

specific management scenario or propose technical requirements specifically tailored to this type 

of unit. Under the proposed rule, these types of units would need to comply with both the 

requirements applicable to the closure of surface impoundments or landfills, and with all of the 

technical requirements applicable to new landfills. Information collected since the proposal 

confirmed that the practice of constructing overfills for the disposal of CCR is conducted with 

some regularity, and raised questions as to whether overfills would be effectively regulated under 

the proposed technical requirements of the rule. In the NODA, to aid in the development of final 

technical requirements, EPA solicited data and information that directly addressed existing 

engineering guidelines or practices applicable to this units, as well as any regulatory 

requirements governing the siting, design, construction, and long-term protectiveness of these 

units for the disposal of CCR.

The Agency received numerous comments on the NODA. The majority of commenters 

agreed that overfills are commonly employed to allow continuing use of CCR disposal sites and 

to avoid the need to develop CCR management units at other sites. Some commenters added that: 

(1) the engineering design of an overfill can increase the stability of the underlying surface 

impoundment or landfill; (2) the use of an overfill facility reduces the need for new infrastructure 

construction; and (3) an overfill avoids having to transport CCR significant distances for off-site 

disposal.

Other commenters mentioned that several states had experience with overfills and have 

applied requirements such as liner systems, monitoring wells, and stormwater modeling on a 
Document submitted to conclude E.O.12866 Review

256

case-by-case basis using best engineering practices. They added that overfills pose unique 

construction and operational issues depending on the site and the characteristics of the 

underlying unit, and that the construction of these units will therefore vary to account for these 

conditions. Commenters identified several issues requiring additional attention during design and 

construction of overfills including seismic and static liquefaction, settlement, foundation

improvement, partial overfills, groundwater upwelling, groundwater monitoring, and wastewater 

infrastructure.

Upon review of these comments and further evaluation, the Agency has concluded that 

while there may be technical issues relating to the design, construction, and maintenance of 

overfills, the technical standards for CCR landfills are sufficiently flexible that no modifications 

are necessary to accommodate such units. For example, while the design and construction of 

groundwater monitoring systems may be technically more challenging, the final standards 

already allow for the construction of a multi-unit system. The performance standards and 

technical specifications laid out in the technical criteria developed for this rule are equally as 

applicable to overfills (and as protective) as to other new units. In essence, EPA is retaining the 

approach from the proposal that overfills will need to comply with both the requirements 

applicable to the closure of surface impoundments or landfills, and with all of the technical 

requirements applicable to new landfills. Thus, overfills cannot be constructed unless the 

underlying foundation—i.e., the existing CCR surface impoundment has first been dewatered, 

capped, and completely closed. And because overfills are considered to be “new CCR landfills,”

the design and construction of such units must comply with the technical requirements that 

address foundation settlement, overall and side slope stability, side slope and subgrade 

reinforcement, and leachate collection and groundwater monitoring system requirements, which 
Document submitted to conclude E.O.12866 Review

257

will all need to be evaluated independent of the underlying CCR disposal unit to ensure that the 

overfill design is environmentally protective. This evaluation must also be certified by a 

qualified professional engineer. 

Under the location standards applicable to new CCR units, subgrade soils must be 

capable of providing stable structural support to the new liner system. An overfill foundation 

composed of unconsolidated materials, such as CCR that is susceptible to slip-plane failure, is an 

unstable area (man-made) and, under provisions of this rule, is therefore a prohibited location for 

new CCR disposal units. The TVA Kingston ash fill failure was at least partly attributable to 

slip-plane failure of saturated CCR that made up the subgrade and foundation beneath the unit. 

Similarly, prudent and standard engineering practice for new CCR landfills requires that 

the base and side slopes of the overlying CCR landfill be able to maintain the structural integrity 

of the unit. If necessary, the subgrade should be reinforced with a geotextile fabric, or otherwise 

improved, to stabilize existing CCR in the underlying unit and to minimize tensile strain in the 

liner system. Slopes should be reinforced to prevent downhill sliding and to protect the leachate 

drainage system.

EPA is aware from comments that at least one facility is consolidating wet CCR in an 

active CCR surface impoundment through placement of dry ash over the wet CCR, and thereby 

converting the impoundment to a dry landfill, without stabilizing the CCR in the unit or capping 

the unit. This practice will no longer be permitted under the final rule criteria. Although no

modifications were determined to be necessary to the individual technical criteria, EPA has 

added specific provisions that clarify the status of overfills, and clearly prohibit construction of a 

CCR landfill over a CCR surface impoundment unless the CCR in the underlying unit has first

been dewatered and the unit is capped and completely closed. Dewatering, capping and closure 
Document submitted to conclude E.O.12866 Review

258

of the underlying CCR unit prior to construction of the overlying CCR landfill renders the CCR 

overfill less susceptible to slip-plane failure. Conversion of an impoundment to a landfill without 

these measures involves a complex construction process that is highly site specific; EPA was 

unable to develop sufficiently objective performance standards that could be independently 

verified outside of a supervised permit program. Because this rule is self-implementing EPA is, 

therefore, prohibiting construction of new CCR landfills over operational CCR surface 

impoundments to prevent the creation of structurally unstable units that could lead to 

catastrophic failures. 

E. Design Criteria - Structural Integrity

Under the design criteria requirements, EPA proposed to establish structural stability 

standards for existing and new CCR surface impoundments and lateral expansions of these units 

based on a combination of existing Federal programs and requirements applicable to dam safety. 

The proposed rule was largely based on the requirements promulgated for coal slurry 

impoundments regulated by the MSHA at 30 CFR 77.216. (See 75 FR 35176.) EPA also 

developed aspects of the proposal based on the USACE and FEMA’s dam safety programs. 

Consistent with the MSHA requirements, EPA proposed that existing and new CCR surface 

impoundments that could impound CCR to an elevation of five feet or more above the upstream 

toe of the structure and have a storage volume of 20 acre feet or more, or that impound CCR to 

an elevation of 20 feet or more above the upstream toe of the structure would be required to 

provide detailed information on the history of construction of the existing CCR surface 

impoundment and to meet certain performance standards. Specifically, facilities would need to 

(1) develop plans for the design, construction, and maintenance of existing impoundments, (2) 

conduct periodic inspections by trained personnel knowledgeable in impoundment design and 
Document submitted to conclude E.O.12866 Review

259

safety, and (3) provide an annual certification by an independent registered professional engineer 

that all construction, operation, and maintenance of impoundments is in accordance with the 

approved plan. 

EPA also proposed to require the facility to obtain certification from a professional 

engineer that the “design of the CCR surface impoundment is in accordance with current, 

prudent engineering practices for the maximum volume of CCR slurry and CCR waste water 

which can be impounded therein and for the passage of runoff from the design storm which 

exceeds the capacity of the CCR surface impoundment. To support this performance standard, 

EPA proposed to require the facility to conduct specific analyses, and to provide information on 

critical structures. This includes the proposed requirements to compute the minimum factor of 

safety for slope stability of the retaining structures of the unit, including the methods and 

calculations used to determine each factor of safety, and to provide information on the physical 

and engineering properties of the foundations of the CCR surface impoundment, any foundation 

improvements, drainage provisions, spillways, diversion ditches, outlet instrument locations and 

slope protections, and area capacity curves. EPA proposed to require more extensive 

information from new CCR surface impoundments addressing the design, construction, and 

maintenance of the new CCR unit, recognizing that such information may not be available for 

existing units. 77 In addition, EPA proposed to require existing and new CCR surface 

impoundments of a specified size to calculate and report the hazard potential classification of the 

 

77 In the proposed rule under proposed § 257.71 – Design criteria for existing CCR surface 

impoundments, the Agency only required the hazard potential classification for which the facility is 

designed and a detailed explanation of the basis for the classification (§ 257.71(d)(1)) “as may be 

available” (§ 257.71(d)). Similarly the computed minimum factor of safety for slope stability of the CCR 

retaining structure(s) and the analyses used in the determination (§ 257.71(d)(11) “as may be available” (§ 

257.71(d)). 
Document submitted to conclude E.O.12866 Review

260

unit. . Finally, EPA proposed that any CCR surface impoundments classified as having a high or 

significant hazard potential, as certified by an independent registered professional engineer, be 

required to develop and maintain an Emergency Action Plan defining the responsible persons 

and actions to be taken in the event of a dam safety emergency. 

The Agency solicited comment on a number of issues relating to the proposed structural 

stability requirements. In particular, the Agency solicited comment on the scope of these 

requirements and whether they should apply to all CCR surface impoundments regardless of 

height and/or storage volume or whether EPA should adopt, as proposed and consistent with the 

MSHA requirements, the size cut-off described in the proposed rule; i.e., impounding CCR to an 

elevation of five feet or more above the upstream toe of the structure and have a storage volume 

of 20 acre feet or more, or impounding CCR to an elevation of 20 feet or more above the 

upstream toe of the structure.

EPA also solicited comment on several alternative strategies for regulating the structural 

stability of CCR surface impoundments in lieu of regulation under RCRA subtitle D. The first 

alternative involved using NPDES permits rather than RCRA regulations to address dam safety 

and structural integrity. The second strategy would eliminate the structural integrity 

requirements from the RCRA subtitle D rule and, instead, have EPA establish and fund a 

program for conducting annual (or at some other frequency) structural stability assessments of 

CCR surface impoundments having a “high” or “significant” hazard potential rating as defined 

by criteria developed by the USACE for the NID. EPA would conduct these assessments and, 

using appropriate authorities already available under RCRA, CERCLA, and/or the Clean Water 

Act, would require facilities to respond to issues identified with their CCR surface 

impoundments. The rationale behind this suggested approach was that annual inspections would 
Document submitted to conclude E.O.12866 Review

261

be far more cost effective than the phase-out of CCR surface impoundments—approximately 

$3.4 million annually for annual assessments, as compared to the $876 million annual cost of a 

rule that also phased out CCR. EPA also solicited comments on the effectiveness of this 

approach in ensuring the structural integrity of CCR surface impoundments. (See for example: 

75 FR at 35176, 35223.)

On October 21, 2010, EPA published a Notice announcing that EPA intended to consider 

the information that had been developed through the Agency’s Impoundment Assessment 

Program as part of the CCR rulemaking. The Notice described the Impoundment Assessment 

Program, and solicited comment on “the extent to which both the CCR surface impoundment 

information collection request responses and assessment materials on the structural integrity of 

these impoundments should be factored into EPA's final rule on the Disposal of Coal 

Combustion Residuals from Electric Utilities.” (See 75 FR 35128.) This included the responses 

to information requests that EPA originally sent to electric utilities, as well as reports and 

materials related to the site assessments developed through the Impoundment Assessment 

Program. At that time, EPA had completed the assessments and the final reports for 53 units. On 

August 2, 2013, EPA published another Notice soliciting public comment on the additional 

assessments that had been completed since the 2010 NODA. In all, this included draft and final 

reports for a total of 522 units and 209 facilities. EPA again solicited comment on the extent to 

which this information should be taken into account as part of this rulemaking. 

EPA received numerous comments on the proposed structural stability requirements. 

Many of these fell within two general areas: (1) EPA’s approach of establishing the structural 

stability requirements, along with EPA’s proposed reliance on MSHA’s size thresholds to 

determine the applicability for the majority of structural stability requirements; and (2) the level 
Document submitted to conclude E.O.12866 Review

262

of detail laid out in the technical criteria themselves. 

With respect to the overall regulatory approach, the majority supported both the concept 

of structural stability requirements for existing and new CCR surface impoundments, and the 

adoption of the MSHA size threshold for complying with the majority of the structural stability 

requirements. EPA received comments from a number of state entities (the Association of State 

Dam Safety Officials (ASDSO) and the Association of State and Territorial Solid Waste 

Management Officials (ASTSWMO)) suggesting that EPA incorporate federal dam safety 

guidelines rather than rely solely on MSHA’s dam safety guidelines. Commenters were concern 

that the MSHA regulations “only exist to protect miners on mine property, and not the 

downstream public.” They urged that any EPA regulation also include consideration of hazards 

to the downstream public. These commenters also requested that EPA “incorporate specific 

safety standards consistent with the Federal Guidelines for Dam Safety,” referencing standards 

contained in FEMA documents 93, 333, 64, 94 and 65. 

Little support was expressed for the alternative strategies presented in the proposal for 

addressing structural stability. Some comments were received suggesting additional alternatives. 

One commenter suggested that EPA consider limiting the volume of “primary containment 

ponds” to 10 acre-feet, reasoning that this provision would likely eliminate much of the concern 

regarding catastrophic failures, like TVA, and actually reduce the amount of slurry released in 

the event of a structural failure. Other commenters argued that EPA should limit the structural

requirements to CCR surface impoundments both meeting the proposed size threshold and 

having a hazard potential classification of "high" or "significant" hazard potential rating based on 
Document submitted to conclude E.O.12866 Review

263

FEMA’s criteria for dam safety.78 Commenters argued that a failure of a CCR surface 

impoundment with a “low hazard potential classification” posed only a low risk for on-site 

economic or environmental losses and would avoid the imposition of costly, arbitrary and 

unnecessary regulatory burdens on the owner or operator. In addition, commenters contended 

that this regulatory approach would be consistent with many state dam regulatory programs that 

apply dam integrity standards only to “high” or “significant” potential hazard facilities and 

would promote consistency with existing state controls.79 Several commenters also suggested 

that EPA consider adding regulatory language or preamble discussion to assist owners or 

operators of CCR surface impoundments in interpreting the specific technical requirements in the 

regulation. 

EPA disagrees with the suggestion that the Agency finalize a mandatory size limitation 

for operating CCR surface impoundments. While limiting the volume of CCR surface 

impoundments to ten acre-feet would limit the volume of CCR released in the event of a 

structural failure, limiting the size of CCR surface impoundments to 10 acre-feet may not always 

be practicable; nor does EPA believe that such a restriction is truly necessary to ensure that the 

section 4004(a) standard will be met. Many CCR surface impoundments are much larger than 

ten acre-feet and have been operating for many years without a structural failure. While EPA 

acknowledges that this fact in no way guarantees that a failure will not occur, the Agency is 

 

78 See: Federal Guidelines for Dam Safety: Hazard Potential Classification for Dams, Federal Emergency 

Management Agency (“FEMA”) (reprinted January 2004). Under the FEMA dam safety classification 

system, a “low hazard potential classification” means that failure or mis-operation of the impoundment 

“results in no probable loss of human life and low economic and/or environmental losses. Losses are 

principally limited to owner’s property.”

79 See e.g., New Mexico Rules and Regulations Governing Dam Design, Construction and Dam Safety 

(e.g., requiring dam site security, an instrumentation plan for monitoring and evaluating dam 

performance, and an operation and maintenance manual and emergency action plan only for dams with a 

high or significant hazard potential); see also NMAC §§ 19.25.12.11(G)-(J).
Document submitted to conclude E.O.12866 Review

264

convinced that the implementation of all of the combined regulatory requirements in this rule 

(e.g., location criteria, structural integrity, inflow design flood controls and inspection 

requirements) provides the necessary safeguards that will ensure that CCR surface 

impoundments are designed, constructed, operated, and maintained to minimize the risks 

associated with a catastrophic release of impounded CCR due to structural failure. While 

limiting the size of CCR surface impoundments will reduce risks because there will be a lower 

volume of waste in the unit, the Agency is not convinced that, in practice, such a requirement 

would meaningfully reduce the risks at many facilities. EPA expects that such a restriction 

would only cause facilities to construct either several small units or a multi-unit system. Failure 

of one unit can lead to progressive failure of other units in the system, and thus, ultimately this 

may not reduce the total volume of waste that could be released into the environment. 

EPA also disagrees that structural stability requirements should only apply to “high” or 

“significant” potential hazard facilities. Similarly, EPA disagrees with commenters that 

structural integrity requirements should only apply to owners or operators of CCR surface 

impoundments that both meet the specified size criteria and have either a high hazard or 

significant hazard potential classification. Even for CCR units with a low hazard potential 

classification, EPA is still concerned with the risk to human health and the environment from any 

structural failure of a CCR unit. As discussed previously in Unit VI.C, the environmental effects 

of the failure of even a low hazard potential impoundment can still be significant, given the size 

of these units, the nature of the material in the unit, and the potential volumes that could be 

released. Contamination of surface waters and groundwater resources is still a significant threat 

when CCR units of this size fail, irrespective of the lower likelihood that a release will affect 

human health, as reflected in the low hazard potential classification. Consequently, one focus of 
Document submitted to conclude E.O.12866 Review

265

this rule is preventing any release, catastrophic or otherwise, of CCR to the environment, and 

limiting all structural stability requirements commenters suggested would be inconsistent with 

this goal. 

The Agency agrees that the final regulation should incorporate provisions that address the 

hazards to the downstream public. Accordingly, the final rule incorporates a number of 

provisions consistent with the FEMA Guidelines, including a requirement that owners and 

operators know each CCR unit’s hazard potential classification, as this is part of owners and 

operators’ responsibility to actively ensure the integrity of their CCR unit(s) and that their 

operations do not endanger human health or the environment. EPA also agrees that the 

requirements should be differentiated based on the potential severity of the consequence posed 

by the unit’s failure, and therefore the hazard potential can be relevant in determining the 

stringency of particular requirements. However, the hazard potential is, at best, only an indicator 

of the potential damage that may be incurred from the structural failure of the unit, and so EPA 

has generally not relied on hazard potential as the sole basis for determining the structural 

integrity requirements that are necessary for a CCR unit.80 Although the hazard potential 

classification can serve as a proxy for the amount of water and CCR that could potentially be 

released to the environment in the event of a CCR surface impoundment failure, the amount of 

water and CCR potentially released is more directly correlated to the actual height and storage 

volume of the CCR surface impoundment. In addition, it is widely recognized that the hazard 

potential classification of an individual unit can often fail to encompass the overall magnitude of 

 

80 For example, EPA relied on hazard potential to trigger the requirement for an Emergency Action Plan, which will 

identify the actions necessary to minimize damage to life and property. As damage to life and property are the 

factors directly addressed in hazard potential classification, reliance on the classification is an appropriate 

determinant for this requirement. 
Document submitted to conclude E.O.12866 Review

266

a release on human health and the environment. CCR surface impoundments can frequently be 

part of a facility’s runoff system that is responsible for routing surface waters to a drainage basin 

or watershed. As previously discussed, the failure of a CCR unit that is part of such a system has 

the potential to inundate downstream surface water units and water bodies, resulting in 

progressive failures of other units, including other CCR surface impoundments at the facility, 

which in turn can have a much greater environmental impact than the failure of just the one unit 

for which a hazard potential classification was made. Using a “height and/or volume” threshold 

to determine the applicability of the structural integrity criteria ensures that CCR units with the 

potential to cause these progressive failures in downstream surface water management units are 

appropriately overseen and regulated. CCR surface impoundments exceeding a specified height 

and/or capacity threshold also pose a higher degree of risk of release of CCR to the environment 

than other types of CCR surface impoundments (e.g., incised or “small” CCR units). For all of 

these reasons, the size of the CCR unit, rather than the hazard potential classification, is the best 

indicator of potential severity of release of CCR to the environment and should therefore be the 

primary basis on which structural integrity criteria are applied. As such, EPA is promulgating, as 

proposed, a regulatory strategy that establishes some requirements for all CCR surface 

impoundments, but relies primarily on size as the basis for determining the majority of the 

specific technical criteria for minimizing risk from structural failure.

Regarding the second major issue presented in the comments, as noted previously, EPA 

received comments requesting the Agency to provide either more specific regulatory language or 

further guidance in the preamble, so that parties could certify that the CCR surface impoundment 

met the rule’s overall performance standard. Commenters contended that guidance would be 

particularly critical if EPA did not establish more specific technical criteria, as owners or 
Document submitted to conclude E.O.12866 Review

267

operators will be vulnerable to lawsuits for non-compliance. In addition, state officials requested 

that EPA adopt more specific standards consistent with those adopted under FEMA’s Federal 

Guidelines for Dam Safety. As discussed throughout this section in more detail, EPA has 

adopted clarifications to the regulation, particularly in the sections on structural stability and 

safety factors, to more precisely lay out the specific technical standards that are considered to be 

the “generally accepted and recognized good engineering practices” that must be met. EPA 

relied extensively on existing MSHA requirements, FEMA’s Federal Guidelines for Dam Safety, 

and guidance issued by the U.S. Army Corps of Engineers, as they were applied throughout 

EPA’s CCR Impoundment Assessment Program, to supplement the technical detail originally 

contained in the proposed rule. EPA has also modified the criteria, where necessary, so they 

better reflect the information and experience developed through the Impoundment Assessment 

Program, e.g., the engineering criteria used to evaluate the CCR surface impoundments and to 

make recommendations to improve the structural stability of the units. 

In this rule, the Agency is finalizing structural integrity criteria to ensure that CCR 

surface impoundments are designed, constructed, operated, and maintained in a manner that 

ensures the structural integrity of the CCR surface impoundment throughout its active life (i.e., 

through closure of the CCR unit), detects actual or potential releases of CCR as early as 

practicable, and prevents catastrophic failures. Many of the requirements have been adopted 

without revision from the proposed rule for some requirements, however, as noted EPA has 

provided additional language to clarify the final regulation. These clarifications have been made 

in response to comments urging EPA to finalize regulatory requirements that were more precise 

or sufficiently objective (i.e., a specific standard of performance) to allow a qualified 

professional engineer to reasonably certify that the requirements of the rule have been met. 
Document submitted to conclude E.O.12866 Review

268

These specific regulatory clarifications are discussed throughout this section. 

A further change is that the final rule requires facilities to periodically reassess several 

elements of the structural integrity performance standards (i.e., re-assess every five years). 

Finally, in contrast to the programs established by MSHA and FEMA, the final rule establishes 

certain minimum requirements for all CCR surface impoundments. This is based on the fact 

that, unlike the dams regulated under other federal programs, the material in all CCR units is 

harmful, so even small releases can present environmental and human health concerns. But the 

majority of the structural integrity requirements vary depending on whether the CCR surface 

impoundment or lateral expansion exceeds particular size thresholds. The rulemaking record 

clearly demonstrates that these larger CCR surface impoundments present a greater risk of 

catastrophic failure, and therefore require a more robust set of regulatory requirements to ensure 

their continue structural integrity. This is consistent with the approach.

These modifications are being made to better reflect the protections necessary to ensure 

that: (1) structural integrity is maintained throughout the operational life of a CCR unit; and (2) 

the risk of catastrophic failure is minimized. The changes being made in this rule have been 

directly influenced by comments received, the observations and the conclusions drawn from 

EPA’s Assessment Program, and the recommendations made by both MSHA and FEMA 

regarding dam safety. They are also generally consistent with the regulatory requirements of 

many other state and other federal agencies regulating dam safety.

1. Overview of Technical Criteria

Owners or operators of all existing and new CCR surface impoundments and any lateral 

expansion of these CCR units are required to: (1) place a permanent identification marker on or 

immediately adjacent to the CCR units with the name associated with the CCR unit and the name 
Document submitted to conclude E.O.12866 Review

269

of the owner or operator of the CCR unit; (2) conduct an initial hazard potential assessment to 

determine the current hazard potential classification of the CCR unit; (3) conduct periodic (i.e., 

every five years) hazard potential re-assessments; (4) develop an Emergency Action Plan (EAP) 

if the hazard potential classification of the CCR unit is classified as either a high- or significant 

hazard potential; and (5) maintain the CCR unit with vegetated slopes or other forms of slope 

protection.

Owners or operators of CCR surface impoundments that either have a height of five feet 

or more and a storage volume of 20 acre feet or more, or a height of 20 feet or more are required 

to comply with the following additional structural integrity criteria: (1) document the design and 

construction of the CCR surface impoundment; (2) conduct an initial structural stability 

assessment; (3) conduct an initial safety factor assessment; and (4) conduct periodic (not to 

exceed five years) structural stability and safety factor assessments.81 Owners and operators of 

CCR units that fail to make the safety factor assessment or fail to meet the factors of safety 

specified in the rule must stop placing CCR in the unit and initiate closure. 

The structural integrity requirements of the final rule require the compilation of 

construction history of the CCR surface impoundment within one year of the effective date of the 

rule. 

Within two months of the effective date of the rule, the Structural Integrity requirements 

(§257.73) state that the owner or operator must install a permanent marker on the CCR surface 

impoundment. This timeframe is being promulgated as proposed, as EPA did not receive 

comments on the timeframe for installation of a permanent marker. 

 

81

 Height means the vertical measurement from the downstream toe of the CCR surface impoundment at 

its lowest point to the lowest elevation of the crest of the CCR surface impoundment.
Document submitted to conclude E.O.12866 Review

270

2. Structural Integrity Requirements Applicable to All CCR Surface Impoundments.

a. Hazard Potential Classification Assessments 

A hazard potential classification provides an indication of the potential for danger to life, 

development, or the environment in the event of a release of CCR from a surface impoundment. 

In this rule, an owner or operator of any existing or new CCR surface impoundment or any 

lateral expansion of a CCR surface impoundment must determine which of the following hazard 

potential classifications characterizes their particular CCR unit.82 These classifications are: a 

high hazard potential CCR surface impoundment, a significant hazard potential CCR surface 

impoundment; and a low hazard potential CCR surface impoundment and are defined as follows:

 High hazard potential CCR surface impoundment means a diked surface impoundment 

where failure or mis-operation will probably cause loss of human life.

 Significant hazard potential CCR surface impoundment means a diked surface 

impoundment where failure or mis-operation results in no probable loss of human life, 

but can cause economic loss, environmental damage, disruption of lifeline facilities, or 

impact other concerns.

 Low hazard potential CCR surface impoundment means a diked surface impoundment 

where failure or mis-operation results in no probable loss of life and low economic and/or 

 

82 Incised CCR surface impoundments are not required to perform a hazard potential classification 

assessment because hazard potential classifications are based on the failure of a dam, diked surface 

impoundment, or other water-retaining structure and the adverse incremental impacts that may result from 

the failure. Because incised CCR surface impoundments, as defined in this rule, do not have a diked 

portion which may fail, the incised CCR surface impoundment cannot have a hazard potential 

classification. Today’s final rule covers CCR surface impoundment failures and releases due to other 

potential failure modes (i.e., which do not pose an immediate catastrophic threat to human health or the 

environment), such as a release through the liner of the unit or through failure of underlying structures, in 

the location restrictions, design criteria, and operating criteria of the rule.
Document submitted to conclude E.O.12866 Review

271

environmental losses. Losses are principally limited to the surface impoundment’s 

owner’s property.

Owners and operators of all CCR surface impoundments must determine each unit’s 

hazard potential classification through a hazard potential classification assessment. Hazard 

potential classification assessments must be certified by a qualified professional engineer and 

documentation must be provided that supports the basis for the current hazard potential rating. 

An initial hazard potential assessment must be conducted within one year of the effective date of 

the rule for existing units and prior to the initial receipt of CCR in the unit for new units or lateral 

expansions. Hazard potential classifications, structural stability assessments, and safety factor 

assessments require significant planning and coordination, such as detailed site-work and 

investigations, modeling and analysis, design and construction planning and implementation, and 

post-construction investigation. Many of these efforts take several months to complete, 

compounded by the fact that much of the work cannot be completed in cold-weather or heavyrain seasons.

As commenters noted, it is imperative that the owner or operator maintain a current 

assessment of a unit’s hazard potential classification, rather than develop a single one-time 

classification “for which the facility was designed.” (See proposed § 257.71(d)(10).) Moreover, 

FEMA recommends that a unit’s hazard potential classification should be reviewed no less 

frequently than every five years in order to take into account changes in the factors that are the 

basis for which a hazard potential classification is made (e.g., changed reservoir or downstream 
Document submitted to conclude E.O.12866 Review

272

development).83 Based on this information, EPA determined that a periodic reassessment of a 

CCR surface impoundment’s hazard potential classification is a necessary component in 

maintaining the accuracy of the unit’s hazard potential classification, as well as the overall safety 

of the unit. Consequently, EPA is requiring the owner or operator of a CCR surface 

impoundment to reassess the hazard potential classifications of their CCR unit and to have that 

classification, certified by a qualified professional engineer, at least every five years. 

EPA has continued to rely on FEMA requirements as the basis for general CCR surface 

impoundment safety requirements, e.g., inflow design flood selection, inspection criteria, 

earthquake analyses and design, developed for CCR surface impoundments for several reasons: 

(1) structural failure risks for CCR surface impoundments are similar to the risks from the larger 

dam universe for which FEMA intends its guidance; and (2) risks to downstream development 

from CCR surface impoundment failures are equal or similar to those presented by other types of 

dams’ failures.

In this rule, hazard potential classifications define the consequences in the event of a 

failure of a CCR surface impoundment. The classification is separate from the structural 

stability of a CCR unit or the likelihood of the impoundment failing. A surface impoundment 

that meets or exceeds all of the structural stability criteria and safety factors of today’s rule 

would still be classified as “high hazard potential” if, in the event of failure, loss of life would be 

likely to occur. The hazard potential classification of the CCR surface impoundments is an 

essential element in determining how to properly design, construct, operate, and maintain a CCR 

 

83 See: Federal Guidelines for Dam Safety: Hazard Potential Classification for Dams, Federal Emergency 

Management Agency (“FEMA”) (reprinted January 2004). Under the FEMA dam safety classification 

system, a “low hazard potential classification” means that failure or mis-operation of the impoundment 

“results in no probable loss of human life and low economic and/or environmental losses. Losses are 

principally limited to owner’s property.”
Document submitted to conclude E.O.12866 Review

273

surface impoundment. As such, the final rule bases the stringency of some technical 

requirements, in part, on the potential for adverse impacts in the failure of the CCR unit, as 

quantified by the hazard potential classification of today’s rule. Specifically, the requirements 

become more stringent as the potential for loss of life and/or property damage increases. This is 

reflected in both the criteria established under the structural stability assessments,--.e.g., where 

the combined capacity of all spillways must adequately manage flow during and following peak 

discharge from the specified inflow design flood based on the hazard potential classification of 

the unit--and in the hydrologic and hydraulic capacity requirements, which are similarly 

specified based on the hazard potential classification of the CCR unit (see §§ 257.73(d)(2)(v); 

257.74 (d)(2)(v) and 257.82 respectively).84 Additionally, high and significant hazard potential 

CCR surface impoundments must develop a written Emergency Action Plan which establishes 

emergency action procedures in the event of a previously defined emergency.

b. Emergency Action Plan

An Emergency Action Plan (EAP) is a document that identifies potential emergency 

conditions at a CCR surface impoundment and specifies actions to be followed to minimize loss 

of life and property damage. Typically an EAP includes: (1) actions the owner or operator will 

take to moderate or alleviate a problem at the CCR unit; (2) actions the owner or operator will 

take, in coordination with emergency management authorities, to respond to incidents or 

emergencies related to the CCR surface impoundment; (3) procedures owner or operators will 

follow to issue early warning and notification message to responsible downstream emergency 

management authorities; (4) inundation maps to allow owners and operators of the CCR unit and 

 

84 A high-hazard potential impoundment, for example, must be designed with sufficient spillway capacity 

to manage flow from the probable maximum flood, whereas a low hazard potential unit need only account 

for a 100 year flood.
Document submitted to conclude E.O.12866 Review

274

emergency management authorities to identify critical infrastructure and population-at-risk sites 

that may require protective measures, warning and evacuation planning; and (5) delineation of 

the responsibilities of all those involved in managing an incident or emergency and how the 

responsibilities should be coordinated and implemented.85 As FEMA guidance suggests, and 

EPA reiterates here, the level of detail in the EAP should be commensurate with the potential 

impact of a surface impoundment failure or other operational incident (e.g., its hazard potential 

classification). A surface impoundment with low potential hazard impact should not require an 

extensive evaluation or be subject to an extensive planning process, while high-hazard and 

significant hazard surface impoundments would typically require a much larger emergency 

planning effort. In addition, high hazard and significant hazard surface impoundments tend to 

involve more entities that must coordinate responsibilities and greater efforts would generally be 

necessary to effectively respond to an incident with such a surface impoundment than to a 

similar incident involving a low-hazard surface impoundment. As such, every EAP must be 

tailored to specific site conditions.

EPA is promulgating, as proposed, a provision that requires any CCR surface 

impoundment that is determined by the owner or operator, through the certification by a 

qualified professional engineer, to be either a high hazard potential CCR surface impoundment 

or a significant hazard potential CCR surface impoundment to prepare and maintain a written 

EAP. While EPA agrees that the level of detail contained in an EAP should be commensurate 

with its hazard potential rating, EPA has concluded that at a minimum, the EAP must: (1) define 

responsible persons and the actions to be taken in the event of a CCR surface impoundment-

 

85 See: “Federal Guidelines for Dam Safety: Emergency Action Planning for Dams,” FEMA 64/July 

2013.A
Document submitted to conclude E.O.12866 Review

275

safety emergency; (2) provide contact information for emergency responders, including a map 

which delineates the downstream area which would be affected in the event of a failure and a 

physical description of the CCR surface impoundment; (3) include provisions for an annual faceto-face meeting or exercise between representatives of the owner or operator of the CCR unit and 

the local emergency responders; and (4) define conditions that initiate implementation of the 

EAP and define emergency response actions which must be implemented upon the detection of 

these conditions, including all persons responsible for the implementation of the emergency 

response actions. The first three of these four requirements were proposed as part of the EAP 

and are being promulgated without revision. The fourth requirement, which requires facilities to 

explicitly define the conditions by which the EAP is activated, was inadvertently omitted from 

the proposal, and is being added to the final rule to ensure that the EAP includes at least the basic 

requirements necessary to function effectively.

The owner or operator must amend the written EAP whenever there is a change in 

conditions that would substantially affect the written EAP in effect, e.g., change in personnel, 

change in emergency responder contact information, a change in the CCR surface 

impoundments’ designation from a significant-hazard potential classification to a high-hazard 

potential classification, or the vertical expansion of the CCR unit (i.e., increase in the amount of 

CCR that potentially could be released.) Consistent with the requirements for hazard potential 

classification reassessments, the Agency is requiring, at a minimum that the EAP be reassessed 

at least every five years. If an owner or operator determines that, as part of it periodic hazard 

potential re-assessment that the unit no longer is classified as a high-hazard or a significanthazard potential classification, but is now classified as a low hazard potential CCR surface 

impoundment, then the owner or operator of the CCR unit is no longer subject to the requirement 
Document submitted to conclude E.O.12866 Review

276

to prepare and maintain an EAP, effective when such documentation is placed into the facility’s 

operating record. If, however, during the reassessment effort it is determined that an existing 

CCR unit classified as a low hazard potential has been re-classified as either a significant-hazard 

or high-hazard potential, the owner or operation must prepare an EAP for the CCR unit within 

six months of completing such a periodic hazard potential re-assessment. 

Although the owner or operator is responsible for developing and maintaining the EAP, 

which must be certified by a qualified professional engineer, the plan should be developed and 

implemented in close coordination with all applicable emergency management authorities, 

including the appropriate local, state, and federal authorities. Generally, these coordination 

efforts, along with the EAP, provide emergency management authorities with the necessary 

information to facilitate the implementation of their responsibilities, and so, it is vital that the 

development of the EAP be coordinated with emergency responders and other entities, agencies, 

and jurisdictions, as appropriate. After the initial EAP has been developed and placed in the 

operating record and on the owner or operator’s internet site, it should be periodically reviewed 

and updated on a regular basis, as it can become outdated and ineffective. While the Agency is 

only requiring the EAP to be re-assessed every five years, it is recommended that the EAP be 

reviewed at least annually for appropriateness, accuracy, and adequacy so as to remain current. 

EPA recommends that the EAP be promptly updated to address changes in personnel, contact 

information and/or significant changes to the facility or emergency procedures. Even if no 

revisions are necessary, the review should be documented. 

The initial EAP must be prepared within 18 months from the effective date of the rule, In 

order to prepare an EAP, the owner or operator must accurately and comprehensively identify 

potential failure modes and at-risk development, and therefore completion of the emergency 
Document submitted to conclude E.O.12866 Review

277

action plan needs to follow the completion of the initial hazard potential classification, structural 

stability assessment, and safety factor assessments, during which this information will be 

generated. 

c. Vegetated Slopes of Dikes and Surrounding Areas

EPA proposed to require both new and existing CCR surface impoundments that exceed 

the MSHA size thresholds to document the slope protection measures that have been adopted and 

to compute the minimum factors of safety for slope stability, in order to support the certification 

from an independent professional engineer that the unit has been designed in accordance with 

“generally accepted engineering standards.” EPA is promulgating the requirement that all CCR 

surface impoundments have adequate slope protection because EPA determined through the 

Assessment Program that slope protection is an essential element in preventing slope erosion and 

subsequent deterioration of CCR unit slopes. EPA is requiring slope protection for all units, not 

just units exceeding the size threshold of the final rule, because EPA has identified that slope 

protection on CCR units is a generally accepted good practice which reduces the occurrence of 

erosion, degradation of surface waters due to run-off from the CCR unit, enhances slope 

stability, and that vegetated cover is an easily accomplished practice in the vast majority of 

climates where CCR surface impoundments are located. In conducting the Assessment Program, 

the protective cover of slopes of the CCR surface impoundment was determined to be relevant to 

the overall condition rating of all units, irrespective of size. This is consistent with FEMA 

guidance, which also lays out specifications for the ideal vegetative cover for a dam. EPA has 

adopted this requirement to be consistent with its findings from the Assessment Program, and in 

response to comments, has elaborated on the slope protection measures necessary to achieve the 
Document submitted to conclude E.O.12866 Review

278

factors of safety. The final rule provides performance standards drawn primarily from FEMA 

guidance, as applied during the Assessment Program.

All CCR surface impoundments are required to be designed, constructed, operated, and 

maintained with adequate slope protection to protect against surface erosion at the site. Slope 

protection is necessary to ensure that dike or embankment erosion does not occur. Additionally, 

slope protection is required of all CCR surface impoundments to maintain the stability of the 

CCR surface impoundment slope under rapid drawdown events86 and low pool conditions of 

water bodies that may abut the CCR surface impoundment and are outside the control of the 

owner or operator, e.g., a natural river which the slopes of the CCR surface impoundment run 

down to and abut. The slope protection can act as a stabilizer in the slope of the embankment 

during rapid drawdown events. Adequate slope protection can be achieved in most climates 

through simple vegetation, typically healthy, dense stand of low-growing grass, or other similar 

vegetative cover. In arid climates where the upkeep of vegetation is inhibited, alternate forms of 

slope protection, including rip-rap, or rock-armor is typically used. Additional slope protective 

measures are available and effective in certain circumstances, including but not limited to rock, 

wooden pile, or concrete revetments, vegetated wave berms, concrete facing, gabions, 

geotextiles, or fascines. 

The owner or operator must ensure that the slopes of the CCR surface impoundment are 

protected from erosion by appropriate engineering slope protection measures. It is recommended 

throughout embankment technical literature that vegetative cover not be permitted to root too 

 

86 This rapid drawdown is not included in the rule’s factors of safety assessments. The protection against 

rapid drawdown requirement of this provision is concerned with the rapid drawdown of adjacent water 

bodies acting upon the downstream slope of the CCR surface impoundment rather than the rapid 

drawdown of the impounded reservoir of the CCR surface impoundment acting upon the upstream slope 

of the CCR surface impoundment. 
Document submitted to conclude E.O.12866 Review

279

deeply, precipitating internal embankment issues. The rule requires a vegetative cover limit to 

prevent the establishment of rooted vegetation, such as a tree, a bush, or a shrubbery, on the CCR 

surface impoundment slope. EPA has concluded that a vegetative cover of no more than six 

inches above the face of the embankment is adequate and is the uppermost limit for vegetative 

cover height for today’s final rule. In developing this requirement, EPA was strongly influenced 

by information contained in the FEMA document entitled, “Technical Manual for Dam Owners: 

Impacts of Plants on Earthen Dams”87 in determining an appropriate vegetative cover height for 

CCR surface impoundments. Six inches represents a vegetative height which prevents any trees, 

bushes, or shrubbery from rooting deeply enough to warrant additional removal measures outside 

of simple mowing. Furthermore, the height prescribed by the final rule represents a maximum 

height of vegetative cover to allow for adequate observation of the slope of the CCR unit during 

inspection. Vegetative cover in excess of six inches above the slope of the dike would prevent 

the adequate observation of the slope of the CCR unit and detection of structural concerns such 

as animal burrows and minor sloughs, amongst others concerns. Consistent with FEMA 

guidance, as applied during the Assessment Program, other slope protection, such as rock 

armoring or vegetated berms, would also be considered adequate.88

2. Structural Integrity Criteria Applicable to CCR Surface Impoundments Exceeding a 

Specific Size Threshold. 

The structural integrity criteria discussed in this section of the preamble apply to existing 

and new CCR surface impoundments and any lateral expansion with: (1) a height of five feet or 

more and a storage volume of 20 acre-feet or more; or (2) a height of 20 feet or more. The rule 

 

87 http://www.fema.gov/media-library-data/20130726-1446-20490-2338/fema-534.pdf

88 http://www.fema.gov/media-library-data/20130726-1446-20490-2338/fema-534.pdf
Document submitted to conclude E.O.12866 Review

280

defines “height” as the vertical measurement from the downstream toe of the CCR surface 

impoundment at its lowest point to the lowest elevation of the crest of the CCR surface 

impoundment. The “downstream toe” is defined as the junction of the downstream slope or face 

of the CCR surface impoundment with the ground surface. Today’s final rule considers the 

lowest elevation of the crest of the CCR surface impoundment to be the maximum storage 

elevation of the reservoir or pool of the CCR unit, e.g., the invert of the lowest-elevation 

spillway. EPA is implementing this size threshold because it comports with thresholds 

established by other federal and state agencies regulating dam integrity and/or safety. 

Specifically, for the implementation of the size threshold of today’s final rule, EPA relied on the 

identical size parameters, i.e., height of five feet and capacity of 20 acre-feet, which is 

promulgated in MSHA coal slurry impoundment regulations in 30 CFR § 77.216.

In the proposed rule, EPA used the size cut-off promulgated by MSHA in their dam 

safety requirements for coal slurry impoundments at 30 CFR Part 77. In proposing this cut-off, 

EPA reasoned that the MSHA requirements affecting coal slurry impoundments were directly 

applicable and relevant to CCR surface impoundments and provided a size threshold that, when 

applied to the rule’s structural integrity criteria, would generally meet RCRA’s mandate to 

ensure protection of human health and the environment by minimizing the potential for 

catastrophic failure. Specifically, EPA proposed that surface impoundments: (1) impounding 

CCR to an elevation of five feet or more above the upstream toe of the structure and can have a 

storage volume of 20 acre-feet or more; or (2) impounding CCR to an elevation of 20 feet or 

more above the upstream toe of the structure would be subject to the structural stability criteria. 

EPA also proposed to define upstream toe as the junction of the upstream slope of the dam with 

the ground surface, with the height of the CCR unit measured from the upstream toe or water-
Document submitted to conclude E.O.12866 Review

281

borne toe of the CCR unit. 

While little comment was received on adopting this size threshold or the accompanying 

definition of upstream toe, the Agency was concerned that the size threshold presented in the 

proposed rule did not reflect standard measuring protocols used by other federal agencies and the 

dam sector in determining the size of a dam or, in the case of today’s rule, surface impoundment. 

Of particular concern to the Agency was the fact that EPA’s own Assessment Program was 

measuring the height of a CCR unit from the downstream toe rather than the upstream toe, which 

was specified in the MSHA regulatory requirement and the subsequent CCR proposed rule. 

A review of MSHA, FEMA and the USACE regulations and guidance, as well as the 

guidance of several state agencies that oversee dam safety, revealed that dam or surface 

impoundment height is more appropriately measured from the downstream and not the upstream 

toe of the unit. EPA based this conclusion on the near-universal position of dam safety guidance 

that the downstream slope height of the dike is of primary concern in the design, construction, 

operation, and maintenance of the dam or surface impoundment. Virtually all of the dam safety 

regulations, including state and federal guidance and regulations, that EPA reviewed considered 

measured dam height to be taken from the downstream slope of the dike. Some of these guidance 

and regulations include FEMA “Federal Guidelines for Dam Safety,” U.S. Army Corps 

“National Inventory of Dams,” and MSHA Metal and Nonmetal Tailings and Water 

Impoundment Inspection requirements in 30 CFR § 56/57.20010.89 This information, coupled 

with the information on the methodology used in the Assessments Program, convinced the 

Agency that a revised description of the CCR surface impoundment size cutoff was necessary, 

specifically requiring the height of the CCR unit to be measured from the downstream toe. 

 

89 http://www.msha.gov/regs/complian/PILS/2013/PIL13-IV-01.asp
Document submitted to conclude E.O.12866 Review

282

a. Design and Construction Information

The first element of the structural integrity criteria applicable to CCR units exceeding the 

specified size threshold requires the owner or operator to compile and place in the operating 

record design and construction information pertaining to the CCR unit. Among other things, this 

provision requires the following documentation to be provided by the owner or operator: (1) the 

name of the owner or operator of the unit; (2) the name of the unit; and (3) any identification 

number assigned by the state. In addition, it requires that the owner or operator identify: (5) the 

location of the CCR unit on a U.S. Geological Survey Map or a topographic map of equivalent 

scale; (6) provide dimensional drawings of the CCR unit with pertinent engineering structures 

and appurtenances identified; (7) describe the purpose of the CCR unit; and (8) identify the name 

and size of the watershed affecting the CCR unit, if any. Detailed information is also required 

documenting: (9) the design and construction of the unit including dates and descriptions of each 

zone or stage constructed; (10) instrumentation used to monitor the operation of the CCR unit, 

(11) spillway and diversion design descriptions and construction specifications; and (12) 

provisions for surveillance, maintenance and repair of the CCR unit. 

While these requirements apply to both existing and new CCR surface impoundments, 

existing CCR surface impoundments are required to compile this information only “to the extent 

available,” within one year of the effective date of the rule. Conversely, new CCR surface 

impoundments or any lateral expansion must compile all of the information listed prior to the 

initial receipt of CCR. For existing CCR surface impoundments, EPA acknowledges that much 

of the construction history of the surface impoundment maybe unknown or lost. EPA’s 

Assessment Program confirmed that many owners or operators of CCR units did not possess 

documentation on the construction history or operation of the CCR unit. Information regarding 
Document submitted to conclude E.O.12866 Review

283

construction materials, expansions or contractions of units, operational history, and history of 

events was frequently difficult for the owners or operator to obtain. The Assessment Program 

also confirmed the Agency’s initial assumption that this information, in many instances, will be 

difficult to compile. Therefore, in today’s rule, EPA is using the phrase “to the extent available” 

and clarifying that the term requires the owner or operator to provide information on the history 

of construction only to the extent that such information is reasonably and readily available. EPA 

intends facilities to provide relevant design and construction information only if factual 

documentation exists. EPA does not expect owners or operators to generate new information or 

provide anecdotal or speculative information regarding the CCR surface impoundment’s design 

and construction history. 

There are several other requirements under the design and construction criteria requiring 

clarification. First, the Agency is amending the requirement that all dimensional drawings of the 

CCR unit (see § 257.73(b)(vii) and § 257.74(b)(vii)) use a uniform scale of one inch equals 100 

feet. After further consideration, EPA has deleted this requirement and has replaced the proposed 

scale of 1 inch equals 100 feet with the phrase “at a scale that details engineering structures and 

appurtenances relevant to the design, construction, operation, and maintenance of the CCR unit.” 

EPA made this change in response to comments arguing that this level of detail was unnecessary. 

EPA agrees that, given the extremely large variety in the size of CCR units, a prescriptive scale 

for all drawings of all CCR units is not necessary in many cases; this level of detail would be 

excessive for most units. The Agency is also clarifying, (see § 257.73(b)(2) and § 257.74(b)(2)) 

that if an owner or operator determines that a significant change has occurred in the 

information/documentation previously compiled under this provision, the owner or operator 

must update the relevant information and place it in the operating record. 
Document submitted to conclude E.O.12866 Review

284

b. Types of Assessments 

A second element of the structural integrity criteria is the requirement for specific 

technical assessments of the CCR unit. Consistent with the requirements outlined in the 

proposed rule, two technical assessments are required for all CCR units exceeding the specified 

size threshold: (1) a structural stability assessment; and (2) a safety factor assessment. The owner 

or operator of an existing CCR surface impoundment is required to conduct an initial assessment 

addressing both structural stability and safety factors within one year of the effective date of the 

rule. New CCR surface impoundments or any lateral expansion of a CCR unit are required to 

complete the initial assessment prior to placing CCR into the unit. Following the initial 

assessments, EPA is also requiring periodic re-assessments of both a CCR surface 

impoundment’s structural stability and factors of safety. EPA proposed to require an annual 

recertification, but in a departure from the proposed rule, EPA is only requiring these reassessments to be conducted on a regular basis, not to exceed once every five years. In making 

this regulatory change, the Agency has relied heavily on the dam safety guidance established by 

FEMA in the document titled, Federal Guidelines for Dam Safety that a formal inspection, 

including”...a review to determine if the structures (i.e., CCR surface impoundments) meet 

current accepted design criteria and practices...” be taken at an interval not to exceed five years. 

EPA has interpreted this guidance to be applicable to both the structural stability assessment and 

the safety factor assessment. 

A demonstration must be completed within the assessment period for the specific type of 

assessment. This means that, within this time frame the owner or operator must demonstrate that 

the CCR unit meets all of the requirements of each type of assessment, as certified by a qualified 

professional engineer. It also means that the owner or operator must have taken all measures 
Document submitted to conclude E.O.12866 Review

285

necessary to bring the unit into compliance with all of the requirements for assessments of 

today’s final rule within the assessment period. If the owner or operator cannot demonstrate that 

the unit meets these factors of safety (or otherwise fails to comply with the structural stability 

requirements) within the appropriate time frame, the unit must initiate closure.

i. Periodic Structural Stability Assessments

In order to ensure the proper upkeep and operation of the CCR unit, the owner or 

operator must demonstrate that the CCR surface impoundment has been designed, constructed, 

operated and maintained to provide structural stability. Specifically, consistent with the proposal, 

the final rule requires the owner or operator to demonstrate that the design, construction, 

operation, and maintenance of the CCR surface impoundment is consistent with recognized and 

generally accepted good engineering practices for the maximum volume of CCR and water that 

can be impounded therein. As discussed previously, EPA has elaborated on this overall 

performance standard in response to comments from the engineers who would be required to 

make these certifications, urging EPA to specify more precisely the standards that must be met. 

Specifically the final rule focuses on the critical structural aspects of the CCR surface 

impoundment that EPA identified in the proposed rule, and identifies the minimum elements that 

a professional engineer must provide engineering details on or otherwise address. In certain 

cases, the final criteria identify specific engineering performance standards. EPA relied on 

existing MSHA requirements, FEMA dam safety guidance, and guidance issued by the U.S. 

Army Corps of Engineers, as applied throughout EPA’s CCR Impoundment Assessment 

Program to develop these criteria. Consistent with the proposal, these demonstrations must be 

certified by a qualified professional engineer. Each of these criteria is discussed in more detail 

below.
Document submitted to conclude E.O.12866 Review

286

In addition to implementing adequate slope protection against erosion, which is a 

structural stability requirement applicable to all CCR units, the owner or operator of a CCR 

surface impoundment exceeding the specified size threshold must demonstrate that the unit, 

including any vertical and lateral expansions, is constructed with “stable foundations and 

abutments.” A stable foundation is an essential element of surface impoundment construction 

and prevents differential settlement of the embankment which can result in adverse internal 

stresses with the embankment cross-section. Soils tend to consolidate when subjected to 

loadings for extended periods, which can lead to strain incompatibility, a phenomena which 

prevents the full development of peak strength of the foundation. The stability of foundations 

and abutments can be determined by engineering monitoring, representative soil sampling, and 

modeling. Similarly, cohesion between the abutments of the CCR surface impoundment and the 

embankment of the CCR surface impoundment is critical. Frequently, CCR surface 

impoundments are subject to cracking and excessive seepage and piping in the groins where the 

abutment and embankment meet. These adverse conditions may lead to further structural 

deficiencies which threaten the safety of the CCR surface impoundment. 

Consistent with general engineering construction methodologies, the structural stability 

assessment also requires the owner or operator to determine whether the CCR surface 

impoundment has been mechanically compacted to a density sufficient to withstand the range of 

loading conditions in the CCR unit.90 Compaction of a dike or embankment is considered 

essential, as the compaction of soils leads to an increase in density and subsequently strength. 

Soil mechanics theory has established that the density of a soil corresponds to the moisture 

 

90 http://www.publications.usace.army.mil/Portals/76/Publications/EngineerManuals/EM_1110-2-2300.pdf
Document submitted to conclude E.O.12866 Review

287

content and strength of the soil. The rule requires the owner or operator make this determination 

for all dikes of a CCR surface impoundment. 

EPA notes that a number of existing voluntary consensus standards are available that can 

be useful in making this determination. For example, ASTM D 698 establishes a performance 

standard of 95% of the maximum standard Proctor density. Similarly, ASTM D 1557 establishes 

a standard of 90% of the maximum modified Proctor density. Alternatively, in certain instances, 

such as soils consisting of more than 30% material retained on the 3⁄4 in. sieve, Proctor testing is 

not appropriate and the relative density criteria can be met. In such cases, EPA recommends a 

70% relative density. These specific soil compaction criteria are ubiquitous throughout 

engineering construction as sufficient to support engineered works based on the requirements. 

They are also consistent with the standards promulgated by the state of New Mexico’s dam 

safety program in order to ensure proper compaction during construction of new CCR surface 

impoundments. 

EPA recognizes that it would be highly difficult for owners or operators of older units to 

certify with any certainty that the unit’s construction meet the specific numeric compaction 

criteria found in the ASTM standards. New units, however, can easily meet these standards, and 

should therefore be designed and constructed to meet the numeric compaction criteria. 

The owner or operator must also design, construct, operate, and maintain the CCR 

surface impoundment spillway or spillways with appropriate material so as to prevent the 

degradation of the spillway, as well as to ensure that the CCR surface impoundment has adequate 

spillway capacity to manage the outflow from a specific inflow design flood. In addition, a 

demonstration must be made that the CCR surface impoundment has been designed, constructed, 

operated, and maintained with inflow design flood controls and/or spillway capacity to manage 
Document submitted to conclude E.O.12866 Review

288

peak discharge during and following inflow design floods. This demonstration is required to 

ensure the CCR surface impoundments will have adequate hydrologic and hydraulic capacity to 

prevent such failures as overtopping and excessive internal seepage and erosion. Spillways must 

be designed to withstand discharge from the inflow design flood without losing their structural 

form and leading to discharge issues, such as erosion or overtopping of the embankment. This 

requirement is covered in more detail in the hydrologic and hydraulic capacity requirements for 

CCR surface impoundments section of this rule.

EPA is not requiring a facility to include any demonstration relating to the potential for 

rapid, or sudden, drawdown loading condition. Rapid or sudden drawdown is a condition in 

earthen embankments in which the embankment becomes saturated through seepage in an 

extended high pool elevation in the reservoir. A threat to the embankment emerges when the 

reservoir pool is drawn down or lowered at a rate significantly higher than the excess poor water 

pressure within the embankment can diminish. Typically, rapid drawdown scenarios are 

considered for embankments with reservoirs used for water supply and management, emergency 

reservoirs, or agricultural supply, in which the reservoir is rapidly discharged from the structure. 

In these scenarios, a high pool elevation is maintained in the reservoir in storage months. 

Subsequently, the water supply is drawn on in months where there is a high demand for the 

reservoir’s contents. This drawing down of the pool can affect the structural stability of the unit. 

However, the management of CCR surface impoundments differs from that of conventional 

water supply, emergency, and agricultural reservoirs. The only instance of a rapid drawdown of 

a CCR surface impoundment which EPA has identified is in the event of a massive release of the 

reservoir of the CCR surface impoundment due to a failure of the dike of the CCR surface 

impoundment. In this instance, a massive release has occurred or is occurring. A subsequent 
Document submitted to conclude E.O.12866 Review

289

failure of the upstream or internal embankment due to this rapid drawdown would only 

precipitate further embankment failure and not any further release of the contents of the 

impoundment, as the contents of the surface impoundment would have already been released. In 

these instances, remediation of a failure in a rapidly drawn-down section would be necessary 

prior to filling of the unit, but is not a concern precipitating a release of impounded contents. 

A second consideration regarding rapid drawdown, however, is the rapid drawdown of a 

water body adjacent to the slope of the CCR surface impoundment which may periodically 

inundate the slope. Many CCR surface impoundments are located in areas in which the 

downstream slope of the CCR surface impoundment runs down to a lake, stream, or river. In 

such instances, rapid drawdown must be considered for the stability of the downstream slope of 

the embankment in the event of a rapid drawdown in the lake, stream, or river pool elevation or 

stage. Because the water ponded against the downstream slope of the CCR surface 

impoundment provides a stabilizing load on the slope of the CCR surface impoundment, the 

rapid or gradual loss of this stabilizing force must be considered in the analysis of the CCR 

surface impoundment. The rule, therefore, requires that existing and new CCR surface 

impoundments and any lateral expansions of such units with a downstream slope that can be 

inundated by an adjacent water body, such as rivers, streams, or lakes, be constructed with 

downstream slopes that will maintain structural integrity in events of low pool or rapid 

drawdown of the adjacent water body. This ensures that the structural integrity of the 

downstream slope of the CCR surface impoundment will be maintained, even though the 

conditions of an adjacent surface water body may be outside the owner or operator’s control. 

ii. Periodic Safety Factor Assessments

As previously discussed, EPA received comment requesting the Agency to supplement 
Document submitted to conclude E.O.12866 Review

290

the proposed technical criteria to assist owners or operators of CCR surface impoundments in 

interpreting the factor of safety determination required by proposed § 257.71(d)(12). EPA 

proposed that facilities compute “a minimum factor of safety for slope stability of the CCR 

retaining structure(s),” and to provide the methods and calculations used to determine each factor 

of safety. In reviewing the proposed requirement, the Agency agrees that further elaboration on 

the requirement is necessary to ensure that engineers can accurately assess a CCR unit’s 

structural stability using factor of safety calculations, and would be valuable to ensure a 

consistent national standard. EPA has therefore revised the criteria to be consistent with the 

criteria developed and used to assess these impoundments as part of the Impoundment 

Assessment Program. 

Accordingly, the final rule requires demonstrations of structural integrity using accepted 

engineering methodologies under specific loading conditions. Owners or operators must conduct 

and have certified by a qualified professional engineer, an initial assessment, supported by the 

appropriate engineering calculations, documenting whether the CCR unit achieves the following 

minimum factors of safety: (1) the calculated static factor of safety under the long-term, 

maximum storage pool loading condition, which must equal or exceed 1.50; (2) the calculated 

static factor of safety under the maximum surcharge pool loading condition, which must equal or 

exceed1.40; (3) the calculated seismic factor of safety, which must equal or exceed 1.00; and (4) 

the calculated liquefaction factor of safety, which must equal or exceed 1.20. In addition to the 

safety factors specified for existing CCR surface impoundments, new CCR surface 

impoundments and any lateral expansion must also comply with a fifth safety factor, the 

calculated static factor of safety under the end-of-construction loading condition, which must 

equal or exceed 1.30. 
Document submitted to conclude E.O.12866 Review

291

The minimum static factors of safety are adopted directly from the U.S. Army Corps of 

Engineer’s Engineer Manual EM 1110-2-1902 entitled, “Slope Stability.” As discussed in more 

detail in Unit III, EPA relied heavily on this manual and applied these specific factors of safety 

during its Impoundment Assessment Program, and it is widely considered the benchmark in the 

dam engineering community for slope stability and methodology and analysis. 

The seismic factor of safety is adopted from review of several dam safety guidance 

documents, including USACE guidance Engineer Circular 1110-2-6061: Safety of Dams-Policy 

and Procedures 2204, Engineer Circular 1110-2-6000: Selection of Design Earthquakes and 

Associated Ground Motions 2008, and Engineer Circular 1110-2-6001: Dynamic Stability of 

Embankment Dams 2004). EPA also reviewed MSHA’s 2009 Engineering and Design Manual 

for Coal Refuse Disposal Facilities, in particular Chapter 7, “Seismic Design: Stability and 

Deformation Analyses.” These documents are viewed by ASDSO, FEMA and MSHA as 

generally accepted guidance on how to conduct seismic stability analyses. EPA chose the factor 

of safety of 1.00 because the 1.00 quantity represents the condition of the slope in which the 

strength of resistance to loading is equal to the anticipated loading stress acting upon the 

embankment, or the value which represents stability under the appropriate loading condition. 

The liquefaction factor of safety is adopted from review of several dam safety guidance 

and liquefaction guidance, including “Soil Liquefaction During Earthquakes,” Idriss and 

Boulanger, Earthquake Engineering Research Institute, 200891, “Geotechnical and Stability 

Analyses for Ohio Waste Containment Facilities,” Ohio EPA, Sept. 14, 2004, Chapter 592, and 

 

91 https://www.eeri.org/products-page/monographs/soil-liquefaction-during-earthquakes-3/

92 http://epa.ohio.gov/portals/34/document/guidance/gd_660.pdf
Document submitted to conclude E.O.12866 Review

292

Federal Guidelines for Dam Safety: Earthquake Analyses and Design of Dams, Document 65,

FEMA May 200593. EPA also reviewed several technical resources regarding soil liquefaction, 

including “Ground Motions and Soil Liquefaction During Earthquakes,” Seed and Idriss, 1982,94

“Liquefaction Resistance of Soils: Summary report from the 1996 and 1998 NCEER/NSF 

Workshops on Evaluation of Liquefaction Resistance of Soils,” Youd and Idriss, 2001,95 and 

Seismic Design Guidance for Municipal Solid Waste Landfill Facilities, US EPA, Office of 

Research and Development, 1995. EPA chose a liquefaction factor of safety of 1.20, identifying 

that consideration of liquefaction potential and post-liquefaction residual strength slope stability 

included several uncertainties in assumptions and analysis which must be accounted for in a 

factor of safety above unity (i.e., 1.00). FEMA guidance explicitly states that “post-liquefaction 

factors of safety are generally required to be a minimum of 1.2 to 1.3.”

In conjunction with this requirement, EPA continues to require periodic re-assessments 

of the safety factor calculations, but as discussed, has modified the frequency to be no less than 

once every five years for all affected CCR units. Periodic reassessments are necessary to 

account for factors that are subject to change and can adversely affect the structural stability of a 

CCR unit, e.g., age, use, volume of material contained within, and to reflect the dynamic nature 

of a CCR surface impoundment and the loads to which the dikes of the CCR surface 

impoundment may reasonably be expected to become subject to Both the requirement to 

periodically reassess safety factor calculations and the five-year time frames are consistent with 

 

93 http://www.ferc.gov/industries/hydropower/safety/guidelines/fema-65.pdf

94 Seed, H. B., and Idriss, I. M., 1982, "Ground Motions and Soil Liquefaction During Earthquakes,"

Monograph No. 5, Earthquake Engineering Research Institute, Berkeley, California, pp. 134.

95 Youd, T. L., Idriss, I. M., 2001, “Liquefaction Resistance of Soils: Summary report from the 1996 and

1998 NCEER/NSF Workshops on Evaluation of Liquefaction Resistance of Soils.” Journal of

Geotechnical and Geoenvironmental Engineering, ASCE.
Document submitted to conclude E.O.12866 Review

293

the guidance set forth by other federal agencies in assessing dam safety, including MSHA, 

FEMA, and the U.S. Army Corps of Engineers. For example, FEMA’s Federal Guidelines for 

Dam Safety explicitly recommends that a dam be formally reassessed at an interval not to exceed 

every five years, and EPA has adopted this minimum frequency of assessment in today’s final 

rule. 

(a). General Safety Factor Assessment Considerations. 

Generally accepted engineering methodologies specify that the determination of the 

structural stability factors of safety specified above is to be calculated by the qualified 

professional engineer using conventional analysis procedures or, if necessary, special analysis 

procedures. Conventional analysis procedures include, but are not limited to, limit equilibrium 

methods of slope stability analysis, whereas, special analysis procedures include, but are not 

limited to, finite element methods, finite difference methods, three-dimensional methods, or 

probabilistic methods. Whichever methodology is used to determine the factors of safety of the 

CCR surface impoundment, the qualified professional engineer must document the methodology 

used, as well as the basis for using that methodology, and the analysis must be supported by 

appropriate engineering calculations. 

Limit equilibrium methods compare forces, moments, and stresses which cause instability 

of the mass of the embankment to those which resist that instability. The principle of the limit 

equilibrium method is to assume that if the slope under consideration were about to fail, or at the 

structural limit of failure, then one must determine the resulting shear stresses along the expected 

failure surface. These determined shear stresses are then compared with the shear strength of the 

soils along the expected failure surface to determine the factor of safety. Limit equilibrium 

methods include, but are not limited to, methods of slices. The most commonly applicable 
Document submitted to conclude E.O.12866 Review

294

method of slices are the ordinary method of slices or Modified Swedish Method, Bishop’s 

Modified Method, force equilibrium methods, Janbu’s method, Morgenstern and Price’s method, 

or Spencer’s Method.

If conventional analysis procedures yield results that indicate complex failure 

mechanisms or the need for estimation of displacements, such as the need to determine internal 

stresses or displacements in and embankment or account for 3-dimensional effects in an 

embankment, special analysis procedures may be necessary to calculate factors of safety. 

Special analysis procedures include, but are not limited to: (1) the finite element method; (2) the 

finite difference method; (3) the three-dimensional limit equilibrium analysis method; or (4) the 

probabilistic method.96

Structural stability factors of safety need to be met in all cross-sections of the CCR 

surface impoundment since the failure of any cross-section of the CCR surface impoundment can 

result in the loss of the reservoir and stored CCR material in the CCR surface impoundment. 

However, it is not necessary to require that the facility to fully analyze and calculate factors of 

safety for all cross sections under the specific loading conditions identified above. Rather, it is 

sufficient to calculate the factors of safety under both static, seismic, and liquefaction loading 

conditions only for the critical cross section of the CCR surface impoundment embankment, 

provided the facility carefully analyzes each cross section to properly identify the critical cross 

section. EPA has adopted this approach because the critical cross-section(s) represents a “mostsevere” case and it is reasonably anticipated that all other cross-sections of the embankment will 

exceed the calculated factors of safety of the critical cross-section(s). The final rule therefore 

 

96 Additional information regarding special analysis methodologies can be found in publications from the 

U.S. Army Corps of Engineers Engineering Publications or geotechnical journals and scholarly articles.
Document submitted to conclude E.O.12866 Review

295

adopts this approach. The final rule defines the critical cross section of the embankment of a 

CCR surface impoundment to be that which is anticipated to be most susceptible amongst all 

cross sections of the embankment to structural failure based on several engineering 

considerations for the given loading condition, such as soil composition of the cross-section, 

phreatic surface level within the cross section, grade of the upstream and downstream slopes of 

the cross section, and presence or lack of reinforcing measures in the cross-section as opposed to 

other cross-sections, such as buttressing or slope protection on the slopes of the cross section. 

Due to the variance of qualitative and quantitative properties of embankment structural strength, 

EPA expects that a prudent engineering analysis will need to consider multiple cross sections to 

ensure proper selection of a critical cross section. 

(b). The Calculated Static Factor of Safety Under the Long-term, Maximum Storage Pool 

Loading Condition. 

It is generally accepted practice to analyze the stability of the downstream slope of the 

dam embankment for steady -state seepage (or steady seepage) conditions with the reservoir at 

its normal operating pool elevation (usually the spillway crest elevation) since this is the loading 

condition the embankment will experience most. This condition is called steady seepage with 

maximum storage pool. The maximum storage pool loading is the maximum water level that can 

be maintained that will result in the full development of a steady-state seepage condition. 

Maximum storage pool loading conditions need to be calculated to ensure that the CCR surface 

impoundment can withstand a maximum expected pool elevation with full development of 

saturation in the embankment under long-term loading. The final rule requires that the calculated 

static factor of safety for the critical cross section of the CCR surface impoundment under the 

long-term maximum storage pool loading condition meet or exceed 1.5.The generally accepted 
Document submitted to conclude E.O.12866 Review

296

methodology for determining the long-term, maximum storage pool loading condition considers 

conditions at the CCR surface impoundment that exist for a length of time sufficient for steadystate seepage or hydrostatic conditions to fully develop within the embankment of the CCR 

unit.97 The maximum storage pool loading needs to consider a pool elevation in the CCR unit 

that is equivalent to the lowest elevation of the invert of the spillway, i.e., the lowest overflow 

point of the perimeter of the embankment. The generally accepted methodology for the 

calculation of the factors of safety uses shear strengths expressed as effective stress and with 

pore water pressures that correspond to the long-term condition. Pore-water pressures should be 

estimated from the most reliable of the following sources: (1) field measurements of pore 

pressures in existing slopes; (2) past experience and judgment of the qualified professional 

engineer; (3) hydrostatic pressure computation for conditions of no flow; or (4) steady-state 

seepage analysis using flow nets or finite element analyses. 

(c). The Calculated Static Factor of Safety Under the Maximum Surcharge Pool Loading 

Condition. 

The maximum surcharge pool loading condition is calculated to evaluate the effect of a 

raised level (e.g., flood surcharge) on the stability of the downstream slope. This ensures that the 

CCR surface impoundment can withstand a temporary rise in pool elevation above the maximum 

storage pool elevation for which the CCR surface impoundment may normally be subject under 

inflow design flood stage, for a short-term until the inflow design flood is passed through the 

CCR surface impoundment. The final rule requires that the calculated static factor of safety for 

the critical cross section of the CCR surface impoundment under the long-term maximum 

 

97 US Army Corps of Engineers “Slope Stability” manual.
Document submitted to conclude E.O.12866 Review

297

surcharge pool loading condition meet or exceed 1.4.

Similar to the long-term, maximum loading condition, a prudent evaluation of the 

maximum surcharge pool loading condition needs to consider conditions at the CCR unit to exist 

for a length of time sufficient for steady-state seepage or hydrostatic conditions to fully develop 

within the embankment of the CCR surface impoundment. The maximum surcharge pool is 

considered a temporary pool that is higher than the maximum storage pool; the maximum 

surcharge loading condition should therefore consider a temporary condition in the pool at which 

the pool exists temporarily above the maximum storage pool elevation in the event of an inflow 

design flood and spillway discharge condition in the reservoir, i.e., above the lowest invert of the 

spillway during the anticipated inflow design flood.

(d). The Calculated Seismic Factor of Safety. 

All CCR surface impoundments, including any lateral expansions that exceed the size 

threshold must meet a seismic factor of safety of equal to or greater than 1.0. EPA has included 

this requirement because the mechanics and response phenomena of geotechnical structures vary 

radically under dynamic loading from those under static loading. Consequently reliance on the 

factors of safety under static loading is not sufficient to evaluate the structural stability of a CCR 

surface impoundment. Standard engineering methodology and guidance support EPA’s 

conclusion that adequate seismic analysis of embanked structures is essential to ensure the 

continued structural stability of a geotechnical structure under dynamic, or seismic, loading is 

warranted.98

As discussed in the section of this preamble addressing the location criteria, all CCR 

 

98 E.g., FEMA’s Federal Guidelines for Dam Safety: Earthquake Analyses and Design of Dams
Document submitted to conclude E.O.12866 Review

298

surface impoundments must also be capable of withstanding a design earthquake without damage 

to the foundation or embankment that would cause a discharge of its contents. To further 

support the location criteria established in this rule, CCR surface impoundments and any lateral 

expansion exceeding a specific height and/or volume threshold must be assessed under seismic 

loading conditions for a seismic loading event with a 2% probability of exceedance in 50 years, 

equivalent to a return period of approximately 2,500 years, based on the USGS seismic hazard 

maps for seismic events with this return period for the region where the CCR unit is located. 

EPA chose the 2% exceedance probability in 50 years event based on its common use in seismic 

design criteria throughout engineering. See for example, ASCE 7 Minimum Design Loads for 

Buildings and Other Structures, International Building Code. Moreover, USGS seismic hazard 

maps, dictate that the life of a structure and the realistic probability of event occurrence be 

considered in the design of lateral force resisting systems for structures. As discussed in the 

Regulatory Impact Assessment, the expected life of a CCR surface impoundment can exceed 50 

years. Consistent with the location criteria for seismic impact zones, EPA adopted 2% as a 

reasonable probability of occurrence. 

Under standard engineering methodologies, seismic analysis includes several procedures 

to adequately analyze the structural strength of a CCR surface impoundment during dynamic, 

i.e., seismic, loading. Such analyses would typically need to include the appropriate 

characterization of ground motions at the site of the CCR surface impoundment for the 2% 

probability in 50 years seismic event99. In addition, the peak ground acceleration (PGA), 

velocity, and displacement should be selected using historic records, site-specific observations, 

 

99 FEMA Doc. 65 “Earthquake Analyses and Design of Dams;” 

http://www.ferc.gov/industries/hydropower/safety/guidelines/fema-65.pdf
Document submitted to conclude E.O.12866 Review

299

or magnitude-distance attenuation relations. Additionally, the analysis would need to include an 

appropriate duration of earthquake, considering accelorograms for the anticipated event. 

Appropriate elastic response spectra should be selected using engineering methodology for 

selection, such as the Newmark-Hall Spectrum or other appropriate published spectra, USGS 

Probabilistic Maps, or site-specific response spectra. 

(e) The Calculated Liquefaction Factor of Safety

All CCR surface impoundments, including any lateral expansions that exceed the size 

threshold and have been determined to contain soils susceptible to liquefaction must meet a 

liquefaction factor of safety of equal to or greater than 1.20. A prudent engineering analysis of 

structural stability also includes a liquefaction potential analysis and analysis of post-liquefaction 

static factors of safety. As discussed previously, liquefaction is a phenomenon which typically 

occurs in loose, saturated or partially-saturated soils in which the effective stress of the soils 

reduces to zero, corresponding to a total loss of shear strength of the soil. The most common 

occurrence of liquefaction is in loose soils, typically sands. The liquefaction FOS determination 

in the final rule is used to determine if a CCR unit would remain stable if the soils of the 

embankment of the CCR unit were to experience liquefaction. Liquefaction analysis is only 

necessary in instances where CCR surface impoundments show, through representative soil 

sampling, construction documentation, or anecdotal evidence from personnel with knowledge of 

the CCR unit’s construction, that soils of the embankment are susceptible to liquefaction. 

EPA has included this requirement because the mechanics and response phenomena of 

geotechnical structures vary radically following induced liquefaction, i.e., post-liquefaction. 

Similar to the requirement for seismic factors of safety, liquefaction factors of safety are 

necessary because reliance on static loading is not sufficient to evaluate the structural stability of 
Document submitted to conclude E.O.12866 Review

300

a CCR surface impoundment. Standard engineering methodology and guidance support EPA’s 

conclusion that adequate liquefaction potential analyses and post-liquefaction residual strength 

slope stability analyses of embanked structures is essential to ensure the continued structural 

stability of a geotechnical structure following dynamic loading.

Under standard engineering methodologies, liquefaction potential analysis and postliquefaction stability analysis includes several procedures to adequately analyze the structural 

strength of a CCR surface impoundment. Because only certain soils, such as loose sands, are 

susceptible to liquefaction, the rule requires only embankments constructed of such soils 

identified through liquefaction potential analysis must meet liquefaction factors of safety. Such 

liquefaction potential analysis would need to include proper soil characterization of the 

embankment soils for soil age and origin, fines content and plasticity index, water content, 

saturation, and maximum current, past, and anticipated future phreatic surface levels within the 

embankment, foundation, or abutments, location beneath the natural ground surface, and 

penetration resistance whether through standard penetration testing (SPT) or, ideally, cone 

penetration testing (CPT). Post-liquefaction stability analysis would need to include detailed 

characterization of the site conditions, identification of the minimum liquefaction-inducing 

forces based on soil characterization, determination of seismic effect on liquefied layers of the 

embankment, and calculation of factors of safety against each liquefied layer of the embankment. 

(f). The Calculated Static Factor of Safety under the End-of-Construction Loading 

Condition. 

The End-of-Construction loading condition must be calculated for new CCR surface 

impoundments to ensure that the CCR surface impoundment can withstand a “first-filling” of the 

embankment, during which time the embankment first become saturated and is subject to 
Document submitted to conclude E.O.12866 Review

301

phreatic flow through the cross-section.

Embankments are typically constructed in layers with soils at or above their optimum 

moisture content that undergo internal consolidation because of the weight of the overlying 

layers. Embankment layers may become saturated during construction as a result of 

consolidation of the layers or by rainfall. Because of the low permeability of fine-grained soils of 

which many embankments are constructed and the relatively short time for construction of the 

embankment, there can be little drainage of the water from the soil during construction: resulting 

in the development of significant pore pressures. Soils with above optimum moisture content will 

develop pore pressures more readily when compacted than soils with moisture contents below 

optimum. In general, the most severe construction loading condition is at the end of construction. 

The final rule requires that the calculated static factor of safety for the critical cross 

section of the CCR surface impoundment under end of construction loading conditions meet or 

exceed 1.30. The End-of-Construction loading condition is analyzed for new construction under 

their initial filling condition, following the completion of construction. Undrained shear strength 

conditions are typically assumed for the End-of-Construction loading condition. Both the 

upstream and downstream slopes of the embankment are analyzed for this condition

e. Failure to Demonstrate Minimum Safety Factors or Failure to Complete a Timely Safety 

Factor Assessment

As previously discussed, the rule requires an owner or operator to document that the 

calculated factors of safety for each CCR surface impoundment achieve the minimum safety 

factors specified in the rule. For any CCR surface impoundment that does not meet these 

requirements, the owner or operator must either take any engineering measure necessary to 

ensure that the unit meets the requirements by the rule’s deadlines, or cease placement of CCR 
Document submitted to conclude E.O.12866 Review

302

and non-CCR waste into the unit and initiate closure of such CCR unit as provided in section 

257.102 within six months. Similarly, if an owner or operator fails to complete the initial safety 

factor assessment or any subsequent periodic factor safety assessment by the deadlines 

established in the rule, the owner or operator must cease placing CCR and non-CCR waste into 

the unit and initiate closure within six months. 

f. Vertical Expansions of CCR Surface Impoundments and Structural Integrity Criteria

It is not uncommon for the owner or operator to raise the crest of a CCR surface 

impoundment to accommodate the additional capacity needs of the facility. The record

documents that CCR surface impoundments are commonly expanded from the original design or 

as-built construction, through such “vertical expansions,” including where a CCR surface 

impoundment changes from a “small” CCR unit (i.e., below the height and/or volume threshold) 

to a “large” CCR unit (i.e., exceeding the height and/or volume threshold). In these situations, 

the owner or operator of the CCR unit becomes subject to additional structural integrity 

requirements as a result of the vertical expansion. Realizing that these newly created “large” 

CCR units will require some time to meet the structural integrity requirements. The Agency is 

allowing one year from the completion of the vertical expansion for the owner or operator to 

comply with the requirements of §§ 257.73 or 257.74, as applicable.

F. Operating Criteria – Air Criteria

EPA proposed to require CCR landfills, CCR surface impoundments and any lateral 

expansion to control the creation of fugitive dust. Specifically, EPA proposed that facilities must 

ensure that fugitive dust either not exceed the standard of 35 μg/m3, established as the level of 

the 24-hour National Ambient Air Quality Standards (NAAQS) for fine particulate matter (PM–

2.5), or any alternative standard established pursuant to applicable requirements developed under 
Document submitted to conclude E.O.12866 Review

303

a State Implementation Plan (SIP) approved or promulgated by the Administrator pursuant to 

section 110 of the CAA (see 75 FR 55175). Consistent with the numerical standard, EPA 

proposed to require that CCR units be managed to control the wind dispersal of dust, and that 

CCR landfills also be required to emplace wet conditioned CCR (i.e., wetting CCR with water to 

a moisture-content that prevents wind dispersal and facilitates compaction, but does not result in 

free liquids) into the unit. EPA also required that documentation of the measures taken to 

comply with the requirements be certified by an independent registered professional engineer. 

EPA proposed these requirements based on the results of a screening level analysis of the risks 

posed by fugitive dust from CCR landfills, which showed that without fugitive dust controls, 

levels at nearby locations could exceed 35 μg/m3, established as the level of the 24-hour PM 2.5 

NAAQS for fine particulate. These measures were also intended to reduce the excessive cancer 

risks associated with the inhalation of hexavalent chromium. This potential risk would apply to 

over six million people who live within the census population data “zip code tabulation areas”

for the 495 rule-affected electric utility plant locations. (See 75 FR 35215.)100

As part of the proposal, EPA solicited comments on the following fugitive dust issues: 

(1) the location of air monitoring stations near CCR landfills or CCR surface impoundments; and 

(2) information on any techniques, such as wetting, compaction, or daily cover that are or can be 

employed to reduce exposures to fugitive dust. The Agency received no information from 

commenters on either of these issues.

 

100 As evidenced in 42 U.S. C. 6971(f), Congress intended that the Occupational Safety and Health Administration 

(OSHA) be able to enforce its regulations to protect workers exposed to hazardous waste and that EPA and OSHA 

would work together to ensure that. EPA is clarifying that it intends that the CCR disposal rule not preempt 

applicable OSHA standards designed to protect workers exposed to CCRs; thus EPA’s final rule on CCR disposal 

will apply in addition to any applicable OSHA standards. The Agency has added specific regulatory language in 

this section to address this intent.
Document submitted to conclude E.O.12866 Review

304

The majority of comments received, however, took issue with the proposed technical 

standard of 35 ug/m3. Commenters argued that, as proposed, the standard would be impossible to 

implement because the Agency provided no information on particle size, form of the standards, 

whether an averaging period is available, point of compliance or how one considers upwind 

sources. More generally, however, commenters argued that the proposed provisions were 

unnecessary because fugitive dust issues were adequately addressed by existing air rules through 

the development and implementation of National Ambient Air Quality Standards (NAAQS), 

such as PM10 and PM2.5. These same commenters acknowledged, however, that if the Agency 

established a criterion to control fugitive dusts, a more appropriate and reasonable standard could 

be based on best management practices or BMPs. To that end, commenters offered information 

suggesting that CCR landfills typically used compaction, regular wetting and temporary covers 

in conjunction with visual air monitoring to effectively control fugitive dust at their facilities,

and that these practices were included in facility operating plans. 

As discussed in the proposed rule, EPA’s decision to address fugitive dust was based on a 

peer review of the 2010 draft Risk Assessment, 2007 NODA stakeholder comments, 

photographic documentation of fugitive dust associated with the management of CCR, Agency 

actions to control fugitive emissions during the clean-up of the December 2008 TVA Kingston 

spill, and OSHA’s Material Safety Data Sheets (now Safety Data Sheets (SDS)) requirements for 

coal ash. These lines of evidence have been bolstered since the proposal, by evidence collected

during the eight 2010 CCR public hearings, where stakeholders provided extensive feedback 

about fugitive dust impacts associated with CCR management at facilities adjacent to their 
Document submitted to conclude E.O.12866 Review

305

residences, and by documented reports on fugitive dust issues provided by citizen groups. 101 The 

stakeholders called for federal oversight to address those instances where complaints were

seemingly ignored by state regulators and/or where state administrative enforcement measures 

failed to compel the utilities to effectively amend their dust emission control management 

practices. The Agency followed up on the complaints with state agencies and compiled a 

preliminary database on documented and alleged fugitive dust damage cases.102

In support of this rule, EPA compiled records of over 20 documented fugitive dust cases, 

in addition to several alleged cases that could not be verified. The documented cases indicate that 

fugitive dust concerns arise in all phases of the CCR life cycle – from conveyor belt transfer at 

the coal-fired power plant, through stockpiling and transport for disposal/beneficial use, and up 

to final disposition. Fugitive dust also is a potential concern associated with both – landfills and 

surface impoundments. Whereas a nexus between fugitive dust impacts and CCR landfill 

operations was to be expected, EPA discovered that fugitive dust was also of concern at CCR 

surface impoundments, either under conditions of windy winter spells affecting CCR exposed 

above or next to the CCR surface impoundment boundary, or due to the total CCR surface 

impoundment evaporation in arid areas. 

Very few studies have been undertaken to test the health impacts caused by fugitive dust 

emissions, and of those few, due to inherent limitations, all failed to prove that fugitive dust was 

 

101 For instance, photographic evidence provided by Susan Holmes, the Bokoshe Environmental Cause 

Group (B.E. Cause), Bokoshe, Oklahoma. See Earthjustice’s brief background coverage at: 

http://earthjustice.org/blog/2011-april/not-having-fun-in-bokoshe-ok, and ABC News’ Oklahoma Town 

Fears Cancer, Asthma May Be Linked to Dump Site, March 29, 2011: http://abcnews.go.com/US/oklahoma-town-fearscancer-asthma-linked-dump-site/story?id=13240312.

102 A compilation of damage cases can be found in the docket supporting this rule.
Document submitted to conclude E.O.12866 Review

306

the cause of the documented health concerns. For example, in the wake of the January 2005 coal 

ash pile collapse at the Rostosky Ridge Road, in Allegheny County, Pennsylvania, both the 

federal and county studies103 failed to test during this period and missed the narrow exposure 

window that would have possibly demonstrated a link between the event and the short-term 

health symptoms (e.g., sore throat, cough, fever, nausea, fatigue, diarrhea, and headaches) 

contracted by residents who ultimately removed approximately 1,500 tons of fly ash from their 

properties immediately after the incident without the benefit of any protective respiratory gear. 

The federal and county studies also found no evidence of long-term arsenic poisoning of the 

tested individuals. For recurring instances of CCR dispersion in the air at the Indian River 

Power Plant, Millsboro, Delaware, three consecutive state studies tentatively established other 

risk factors as the probable cause for a lung cancer cluster in a down-wind location of the 

presumable source term (CCR fugitive dust blowing of a landfill and stack emissions).104 Critics 

claim that these studies used too small of a sample, and were not designed to capture the impact 

of long-term exposure to pollution.105

Nevertheless, in eleven other cases, states adopted measures to address concerns from 

fugitive dust emissions; these included conducting lung-cancer cluster and other health studies, 

 

103 (i) Coal Fly Ash Landslide, Forward Township, Allegheny County, Pennsylvania, ASTDR Health 

Consultation June 1, 2006: 

http://www.atsdr.cdc.gov/HAC/pha/CoalFlyAshLandslide/CoalFlyAshLandslideHC060106.pdf

(ii) Results of the Health Investigation Following Fly Ash Contamination in Forward Township, 

Allegheny County, Pennsylvania, Allegheny County Health Department, July 2005: 

http://academics.rmu.edu/faculty/short/research/arsenic/ACHD-Arsenic-2005.pdf.

104 Millsboro Inhalation Exposure and Biomonitoring Study. State of Delaware Department of Natural 

Resources and Environmental Control, Department of Health and Social Services, Dover (RTI Project 

0213061), DE, May 2013: 

http://www.dnrec.delaware.gov/Admin/Documents/Millsboro_Inhalation_Exposure_and_Biomonitoring_

Study_Final_Repor_05282013.pdf

105 Critic chides cancer study: Indian River plant results called lame. Delawareonline, May 28, 2013: 

http://www.delawareonline.com/article/20130528/NEWS/305280081/
Document submitted to conclude E.O.12866 Review

307

conducting particle dispersion studies, issuing Notices of Violation and Consent Orders to the 

responsible facilities, waiving landfill cover exemptions, and requiring dust management plans 

for newly permitted CCR landfills. In addition, in several instances, citizens filed lawsuits or 

reached an out-of-court settlement with the primary responsible party; and in one case, OSHA 

imposed a steep fine on the owners of a facility manufacturing abrasive blasting and roofing 

materials from slag produced at a nearby coal-fired power plant, for willfully exposing their 

workers to dangerously high levels of hazardous dust, and for failing to provide adequate 

breathing protection and training for workers at the facility. According to stakeholder allegations, 

fugitive dusts generated by these same materials also adversely impacted residents in the 

facility’s immediate vicinity. 

As previously stated, many commenters argued that the proposed numeric particulates 

standard was incompatible with the air quality requirements established under the States’ 

Implementation Plans (SIPs) or with provisions set up by the states in their Title V Clean Air 

Permits to the power producers. In addition, the commenters argued that the proposed standard 

lacked technical details to facilitate effective implementation, and that implementation of the 

standard required specialized equipment and advanced training to carry out a judicious reading 

and interpretation of opacity, a proxy measure for the level of fugitive dust emissions. In light of 

these comments, EPA re-evaluated the existing CAA standards applicable to these units; 40 CFR 

§ 70.2 identifies fossil-fuel-fired steam electric plants of more than 250 million BTU/hour heat 

input as potential sources of fugitive dust (PM sources) that must be covered by state permitting, 

and 40 CFR part § 70.3 stipulates that “Fugitive emissions from a part 70 source shall be 

included in the permit application and the part 70 permit in the same manner as stack emissions, 

regardless of whether the source category is included in the list of sources contained in the 
Document submitted to conclude E.O.12866 Review

308

definition of major source.” Based on these applicable CAA requirements, the Agency agrees

that the adoption of a PM standard under the final rule would entail a potential for duplication or 

inconsistency with applicable state-established standards in SIP permits. 

EPA also acknowledges the challenges involved in measuring the proposed compliance 

standard. Because fugitive dust is emitted from non-point sources, it cannot be easily measured 

by conventional methods. Usually, regulations developed by the states to control fugitive dust 

stipulate that no person or source shall cause or allow, from any activity, any emissions of 

fugitive particulate matter that are visible to an observer who looks horizontally along the 

source’s property line. A quantitative measurement of fugitive dust levels (EPA’s Reference 

Method 9) would require measuring opacity, which, as the commenters noted, necessitates 

specialized technical training, trainee certification, and judicious application of instrumentation. 

Therefore, rather than requiring a potentially redundant and challenging-to-implement 

quantitative standard, EPA is substituting a performance standard for fugitive dust control. This 

standard requires owners or operators of a CCR unit to adopt measures that will effectively 

minimize CCR from becoming airborne at the facility, including CCR fugitive dust originating 

from CCR units, CCR piles, roads, and other CCR management activities. The Agency considers 

this standard to be consistent with the intent of the proposed rule, with the added advantage of 

allowing facilities the flexibility to determine the appropriate measures to achieve regulatory 

compliance at their individual site. This standard and the accompanying regulatory requirements 

supporting its implementation, will achieve the statutory obligation of “no reasonable 

probability of adverse effects on human health and the environment.” 

As in the proposal, the Agency is also requiring documentation of the measures taken to 

comply with the technical standard in a “CCR fugitive dust control plan” (herein referred to as 
Document submitted to conclude E.O.12866 Review

309

“plan”). Consistent with the proposal, the plan must be certified by a qualified professional 

engineer and placed in the operating record and on the owner or operators publicly accessible 

internet site. The plan requires owners or operators to elaborate on the types of activities 

applicable and appropriate for the conditions at the facility that will be employed to minimize 

CCR from becoming airborne at the facility. Examples of control measures that may be 

appropriate include: locating CCR inside an enclosure or partial enclosure; operating a water 

spray or fogging system; reducing fall distances at material drop points; using wind barriers, 

compaction, or vegetative covers; establishing and enforcing reduced vehicle speed limits; 

paving and sweeping roads; covering trucks transporting CCR; reducing or halting operations 

during high wind events; or applying a daily cover. 

The initial plan must be completed by the effective date of the rule (i.e., within six 

months of publication). Because this is an initial plan, and because it must be completed within 

a short time frame, EPA acknowledges that the facility may only be able to present its initial 

judgment of the measures that it anticipates are likely to be effective based on the information 

that is readily available within this six month time frame. EPA anticipates that owners or 

operators may need to revise the plan as they gain additional information and experience 

implementing the regulations. In recognition of this, the final rule also requires that the CCR 

fugitive dust control plan include a description of the procedures the owner or operator will 

follow to periodically assess the effectiveness of the control plan. Consistent with other plans 

required in this rule, the owner or operator may amend the written CCR fugitive dust control 

plan at any time. However, the owner or operator must amend the written plan whenever there is 

a change in conditions that would substantially affect the written plan in effect, such as the 

construction and operation of a new CCR unit. The plan and any subsequent amendments must 
Document submitted to conclude E.O.12866 Review

310

be certified by a qualified professional engineer.

In addition, the Agency is promulgating with a slight modification the requirement for 

owners and operators of all CCR landfills and any lateral expansion to emplace CCR as 

conditioned CCR, as well as the definition of conditioned CCR. Conditioned CCR has been 

defined to mean CCR wetted with water to a moisture content that will prevent wind dispersal, 

but will not result in free liquids, consistent with the definition in the proposed rule. In response 

to several commenters’ requests and upon further evaluation the Agency is allowing that in lieu 

of water, CCR conditioning may be accomplished with an appropriate chemical dust suppression 

agent. 106 As with other requirements of this rule, in order to ensure that the provisions of the 

fugitive dust criteria are maintained throughout the operating life of the CCR unit, the Agency is 

requiring that the owner or operator prepare an annual CCR fugitive dust control report, 

describing the actions taken to control CCR fugitive dust, a record of all citizen complaints, and 

a summary of any corrective measures taken. The first annual report must be completed no later 

than 14 months after placing the initial CCR fugitive dust control plan in the facility’s operating 

record. The owner or operator has completed the annual CCR fugitive dust control report when 

the plan has been placed in the facility’s operating record. 

The general public, as well as the Agency, is highly concerned with potential risks 

associated with CCR fugitive dusts. This was readily apparent during the public hearings and 

from the many comments received on this issue. The Agency continues to receive information 

regarding this human health and environmental concern. While the subtitle D provisions of this 

 

106

 Spray-on adhesives, surfactants, aqueous foamers, humectants (calcium, magnesium, ad sodium 

chloride and their mixtures), and polymer solutions and emulsions. See, for instance “The Role of 

Chemicals in Controlling Coal Dust Emissions/Benetch, Inc. http://www.benetechglobal.com/ or 

Peterson, Edwin. “An Aid to Fugitive Materials Control in Coal Ash Applications” presented at the 

World of Coal Ash (WOCA) conference – May 9-12, 2011 in Denver, Colorado.
Document submitted to conclude E.O.12866 Review

311

rule lack permitting oversight mechanisms to control fugitive dust from CCR units, it is clear to 

the Agency that additional substantive actions was needed to facilitate citizen suit enforcement 

of this criteria. Consequently, the Agency is adding a specific requirement to the CCR fugitive 

dust control plan to require owners and operators of all CCR units to develop and implement 

formal procedures to log citizen complaints involving CCR fugitive dust events. These 

complaints must, then, be included as part of the annual CCR fugitive dust control report. This 

report must be placed in the operating record and on the owner or operator’s publicly accessible 

internet site. Promulgation of these measures will subject the owner or operator of the CCR 

disposal facility to public and state scrutiny, and create an incentive for the owner or operator of 

the CCR disposal facility to improve compliance with the fugitive dust control requirements.

G. Operating Criteria – Run-on and Run-off Controls for CCR Landfills

EPA’s proposal required owners or operators of CCR landfills and all lateral expansions 

to design, construct and maintain a run-on control system to prevent flow onto the active portion 

of these units during the peak discharge from a 24 hour, 25-year storm. As described in the 

proposed rule, run-on controls are designed to prevent erosion, which may damage the physical 

structure of the landfill, prevent the surface discharge of CCR in solution or suspension; and to 

minimize the downward percolation of run-on through wastes, creating leachate. Similarly, EPA 

proposed run-off controls in order to collect and control, at a minimum, the water volume 

resulting from a 24-hour, 25-year storm. This standard was proposed in order to protect surface 

waters from contamination. Under the existing 40 CFR part 257 requirements, to which CCR 

units are currently subject, run-off must not cause a discharge of pollutants into waters of the

United States that is in violation of the National Pollutant Discharge Elimination System 

(NPDES) under section 402 of the Clean Water Act. EPA did not propose to revise the existing 
Document submitted to conclude E.O.12866 Review

312

requirement, but merely incorporated it for ease of the regulated community.

The Agency proposed the 24-hour period because it was a timeframe that included storms 

of high intensity with short duration and storms of low intensity with long duration. EPA 

believed that this was a widely used standard that had been incorporated into the hazardous 

waste landfills and MSW landfills regulatory requirements. At the time, EPA had no 

information that warranted a more restrictive standard for CCR landfills. EPA received no 

significant comment on the proposed requirements, and for the most part, is adopting the 

proposed requirements without revision. However, in an effort to clarify and provide more 

direction to the owner or operator and the certifying qualified professional engineer, the Agency 

has added additional regulatory language that more specifically describes the technical criteria 

established under this section of the rule.

The run-on and run-off (RORO) controls of the final rule require that the owner or 

operator prepare the initial run-on and run-off control system plan within 18 months of the 

effective date of the rule. Run-on and run-off control system plan reporting may require design, 

construction, and post-construction implementation. In instances where RORO capacity is 

insufficient, installing additional capacity may involve construction of diversion structures such 

as swales or ditches. Many of these efforts may require several months of design and 

construction, compounded by the fact that much of the work cannot be completed in coldweather or heavy-rain seasons.

1. Run-on and Run-off Controls for CCR Landfills and All Lateral Expansions107

 

107 In the proposed rule under the RCRA subtitle D option, EPA jointly proposed run-on and run-off 

requirements for CCR landfills and CCR surface impoundments under proposed § 257.81. In this final 

rule, EPA has modified the “run-on and run-off” requirements and is providing separate requirements for 
Document submitted to conclude E.O.12866 Review

313

All CCR landfills and all lateral expansions must be designed, constructed, operated, and 

maintained with a run-on control system to prevent flow onto the active portion of the CCR unit 

from the peak discharge from a 24 hour, 25-year storm and a run-off control system to collect 

and control at least the volume of water resulting from a 24-hour, 25-year storm from the active 

portion of the CCR disposal unit.

108

Consistent with the proposal, the rule requires the owner or operator of a CCR landfill or 

lateral expansion to prepare an initial run-on and run-off control system plan for the CCR unit. 

For existing CCR landfills, the plan must be prepared by the owner or operator no later than one 

year from the effective date of the rule. For new CCR landfills and any lateral expansion of a 

CCR landfill, the plan must be prepared no later than the date of initial placement of CCR in the 

landfill or lateral expansion. The plan must document how the run-on and run-off control 

systems have been designed and constructed to meet the requirements of rule and must be 

supported by appropriate engineering calculations. The run-on and run-off control system plan 

must be certified by a qualified professional engineer and is considered prepared when the owner 

or operator has placed the plan in the facility’s operating record. 

The rule also provides for the owner or operator to amend the plan at any time (e.g., 

prior to receipt of CCR in the CCR unit, during the operating life of the CCR unit, during closure 

of the CCR unit, or following closure of the CCR unit) provided the revised plan is placed in the 

 

CCR landfills and CCR surface impoundments. CCR surface impoundments are now subject to the 

hydrologic and hydraulic capacity requirements at § 257.82. This new section of the rule more 

appropriately addresses flow management issues at CCR surface impoundments. 

108 Under existing Part 257 requirements, to which CCR units are currently subject, runoff must not cause 

a discharge of pollutants into waters of the United States that is in violation of the National Pollutant 

Discharge Elimination System (NPDES) under section 402 of the Clean Water Act (40 CFR 257.3-3). 

EPA did not propose to revise this requirement but is merely incorporating it here for ease of the 

regulated community.
Document submitted to conclude E.O.12866 Review

314

facility’s operating record. The owner or operator must, however revise the plan whenever there 

is a change in the conditions that would substantially affect the written plan in effect (e.g., 

closure of an existing portion or cell of the CCR landfill, resulting in a possible change in the 

size of the “active portion” of the CCR landfill). 

In addition, consistent with other provisions in this rule, the Agency is requiring that the 

run-on and run-off control system plan be reviewed, and where necessary, revised or updated at 

least every five years. The Agency is specifying this periodic review in order to address factors 

having the potential to influence the run-on and run-off control system. Among other things, 

CCR landfills can be subject to build-out, operational changes, and surface cover changes, all of 

which have the potential to significantly alter run-on and run-off flows to and from the active 

portion of the CCR landfill. Changes in storm intensity and duration, as well as upstream 

catchment area characteristics, can alter flows that may significantly affect a previously adequate 

run-on and run-off control system. A mandated five year review of a control system plan is 

consistent with accepted good engineering practices and protocols for proper maintenance of 

operational systems supporting the overall performance of a CCR landfill. IT is also consistent 

with the proposed requirement that an owner or operator “maintain” the run-on and run-off 

control system. EPA interprets this to require the owner or operator to ensure that the run-on and 

run-off control system is kept in a condition that meets the requirements of the rule, i.e., that the 

run-on and run-off control system both prevents flow onto the active portion of the unit during 

the peak discharge from a 24 hour, 25-year storm and collects and controls at least the water 

volume resulting from a 24 hour, 25 year storm event for the duration of the CCR landfill’s 

operational life. A requirement to conduct a review of the control plan at least once every five 

years merely provides an explicit mechanism to ensure this occur, in a manner that facilitates 
Document submitted to conclude E.O.12866 Review

315

citizen and state oversight. 

The date of preparing of the initial plan is the basis for establishing the deadline to 

complete the first subsequent plan; i.e., the subsequent plan must be completed within five years 

of the prior plan. The owner or operator may complete any required plan prior to the required 

deadline and must place the completed plan into the facility’s operating record within the 5-year 

time frame. A qualified professional engineer must certify that the run-on and run-off control 

system plan, including any subsequent amendments, meets the run-on and run-off control system 

requirements of today’s final rule. 

a. Run-on control 

Consistent with the proposal, EPA is defining run-on to mean any liquid that drains over 

land onto any part of a CCR landfill or any lateral expansion of a CCR landfill. In surface water 

hydrology, run-on is a quantity of surface runoff, or excess rain, snowmelt, or other sources of 

water, which flows from an upstream catchment area onto a specific downstream location. This

rule requires that the CCR landfill be designed, constructed, operated, and maintained to prevent 

flow onto the active portion of the CCR landfill during the peak discharge from a 24 hour, 25-

year storm. EPA has adopted this requirement to minimize the amount of surface water entering 

the CCR landfill and to minimize the disruption of the CCR landfills operation due to storm

water inflow. Uncontrolled or undesirable storm water run-on may have significant impacts on 

the stability of the slopes of a CCR landfill and continued safe operation of the CCR landfill, due 

to such phenomena as erosion and infiltration.

b. Run-off control 

EPA has adopted the definition of run-off from the proposal without revision. Run-off

means any liquid that drains over land from any part of the CCR landfill. Effectively, run-off is 
Document submitted to conclude E.O.12866 Review

316

the portion of rainwater, snowmelt, or other liquid which does not undergo abstraction, such as 

infiltration, and travels overland. Typically, runoff is the product of the inability of water to 

infiltrate into soil due to saturation or infiltration rate capacity being exceeded. The rule requires 

that the CCR landfill be designed, constructed, operated, and maintained to collect and control at 

least the water volume resulting from a 24-hour, 25-year storm. The owner or operator must 

design, construct, operate, and maintain the CCR landfill in such a way that any run-off 

generated from at least a 24-hour, 25-year storm must be collected through hydraulic structures, 

such as drainage ditches, toe drains, swales, or other means, and controlled so as to not adversely 

affect the condition of the CCR landfill. EPA has promulgated these requirements to minimize 

the detention time of run-off on the CCR landfill and subsequently minimizing infiltration into 

the CCR landfill, to dissipate storm water run-off velocity, and to minimize erosion of CCR 

landfill slopes. An additional concern with run-off from CCR landfills is the water quality of the 

run-off, which may collect suspended solids from the landfill slopes. EPA acknowledges that the 

run-off requirements will also minimize the amount of run-off related pollution generated by the 

landfill run-off. 

c. Run-on and Run-off Control System Plan

The owner or operator of any CCR landfill must prepare an initial run-on and run-off 

control system plan documenting, with supporting engineering calculations, how the control 

systems have been designed and constructed to meet the requirements of the rule. This has been 

adopted without revision from the proposal. In most cases, EPA expects this documentation will 

include in addition to the supporting engineering calculations, references and drawings regarding 

the identification of the 24 hour, 25 year storm for the location of the CCR landfill, a 

characterization of the rainfall abstractions, including but not limited to depression storage and 
Document submitted to conclude E.O.12866 Review

317

infiltration, the selection and basis of an appropriate runoff model, the selection and basis of an 

appropriate run-on or run-off routing model, and the selection and design of an appropriate runon and run-off management system(e.g., swales, ditches, retention or detention ponds). 

Consideration of the above factors would generally constitute a comprehensive review of the 

hydraulic and hydrologic processes associated with the design of a run-on and run-off control 

system plan. EPA recognizes that over time, any number of factors, e.g., expansion of the 

facility, could affect a change in the run-on and run-off control system plan. Consequently in the 

final rule EPA is providing for flexibility in this area by stating that the plan can be amended by 

the owner or operator at any time during the life of the CCR landfill, provided the amendments 

are placed on the facility’s publicly available internet site.

H. Operating Criteria – Hydrologic and Hydraulic Capacity Requirements for CCR Surface 

Impoundments.

As discussed in the previous section, EPA proposed to require owners or operators of 

CCR landfills to design, construct, operate, and maintain: (1) a run-on control system to prevent 

flow onto the active portion of the unit during the peak discharge from a 24-hour, 25-year storm; 

and (2) a run-off control system to collect and control, at a minimum, the water volume resulting 

from the same 24-hour, 25-year storm. EPA also proposed to apply these same run-on and runoff requirements to all CCR surface impoundments and lateral expansions. 

Commenters overwhelmingly disagreed with EPA’s decision to apply the same run-on 

and run-off requirements to both CCR landfills and CCR surface impoundments, arguing that a 

"control system to prevent flow onto the active portion of the surface impoundment" was at odds 

with a commonly employed practice of using CCR surface impoundments to manage incoming 

storm water and other inflow. While some commenters reasoned that preventing run-on may be 
Document submitted to conclude E.O.12866 Review

318

appropriate for CCR landfills and CCR surface impoundments surrounded by above-ground 

dikes, the proposed requirement was entirely inappropriate for units specifically designed to 

retain storm water from an adjoining watershed or to operate as part of a facility’s overall storm 

water management system. Numerous commenters suggested that instead of the run-on 

prevention provision for CCR surface impoundments, EPA adopt a requirement specifying that 

CCR surface impoundments be designed to accommodate “peak discharge events.” Other 

commenters argued that storm water run-on controls were only appropriate during and after the 

closure of CCR surface impoundments; while still other commenters suggested that EPA remove 

entirely the run-on and run-off requirements because CCR surface impoundments were typically 

designed to impound and discharge storm water flow far in excess of a 25 year/24 hour storm 

event. 

In evaluating the arguments against the requirements to prevent flow onto the CCR 

surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for 

selecting and accommodating hydraulic and hydrologic inflow and outflow as well as the 

application of this guidance to the CCR surface impoundments evaluated as part of EPA’s 

Assessment Program.109 A review of FEMA guidance confirmed commenters’ contentions that 

managing flow both to and from dams and impoundments was a widely used practice, and a 

preferable management strategy for accommodating storm water flows. This was further 

confirmed by observations made during EPA’s Assessment Program; EPA frequently observed 

units designed to detain or retain storm water inflows of an upstream catchment area to manage 

CCR, and/or to receive storm water inflow as part of the facility’s overall storm water 

 

109

 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow 

Design Floods for Dams” in evaluating the adequacy of the CCR surface impoundment’s hydrologic and 

hydraulic capacity during its assessment effort.
Document submitted to conclude E.O.12866 Review

319

management system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy 

of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these 

assessments, EPA considered a number of factors including operating freeboard, catchment area, 

hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence 

and capacity, and unit operating procedures to make this determination. The adequacy of the 

capacity was determined using FEMA guidance for selecting and accommodating inflow design 

floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for 

CCR surface impoundments rather than “run-on” and “run-off” is more directly applicable to the 

hydraulic and hydrologic capacity of CCR surface impoundments to adequately manage both the 

inflow and outflow from a design flood.) 

During its assessment effort, EPA also found that, contrary to commenter’s arguments 

CCR surface impoundments are often not designed to address flood in excess of a 24 hour, 25-

year storm event. Rather many CCR surface impoundments were deficient in their hydrologic 

and hydraulic capacity requirements due to factors such as lack of operating freeboard, 

misunderstanding of the actual contributory area, lack of documentation, undersized decant 

structures, undersized spillways, and lack of spillways. 

EPA also disagrees with the comment asserting that storm water controls are only 

appropriate during and after closure of CCR surface impoundments. Hydrologic and hydraulic 

capacity, as determined by an effective design flood control system, is an essential element of the 

overall structural integrity and safety of a CCR surface impoundment. CCR surface 

impoundments are subject to any number of stresses throughout their operational life; one of the 

most common causes of a dike or embankment failure being the inability of the CCR unit to 

adequately pass or manage flood flows resultant from direct or indirect precipitation. These 
Document submitted to conclude E.O.12866 Review

320

failures can occur at any point in the CCR unit’s life, not solely during and after closure, and are 

usually due to inadequate hydrologic and hydraulic capacity, leading to internal erosion due to 

seepage and piping, erosion of spillways, overtopping erosion, and overstressing of the 

embankment. Furthermore, according to the U.S. Bureau of Reclamation, a common dam failure 

mode is due to overtopping, accounting for 30% of the failures in the U.S. over the last 75 

years.110 Overtopping is the direct result of lack of adequate hydrologic and hydraulic capacity

of a dam or surface impoundment. Therefore, EPA is not modifying the regulation as suggested 

by the commenter.

In light of comments received, observations made during EPA’s Assessment Program, 

and guidance developed by FEMA, EPA has concluded that it was inappropriate to propose to 

prohibit all run-on discharge or inflow from storm water to CCR surface impoundments. EPA 

has also concluded that run-on and run-off criteria are inappropriate for CCR surface 

impoundments, and that a more appropriate standard involves determining the hydrologic and 

hydraulic capacity of a unit, measured by its inflow design flood or IDF. Therefore, EPA is 

amending the proposed run-on and run-off requirements for CCR surface impoundments to 

require owners or operators of all CCR surface impoundments to design, construct, operate, and 

maintain hydraulic and hydrologic capacity to adequately manage flow both into and from a 

CCR surface impoundment during and after the peak discharge resulting from the inflow design 

flood, based on the Hazard Potential Classification of the CCR surface impoundment. 

The final rule requires the preparation of the initial inflow design flood control system 

plan within 18 months of the effective date of the final rule. In many cases, inflow design flood 

 

110 http://www.usbr.gov/ssle/damsafety/Risk/BestPractices/16-FloodOvertoppingPP20121126.pdf
Document submitted to conclude E.O.12866 Review

321

control system plan reporting may require design, construction, and post-construction 

implementation in order to provide sufficient hydrologic and hydraulic (H/H) capacity for the 

CCR unit. In instances where H/H capacity is insufficient, installing additional capacity may 

involve spillway construction or decant structure construction or installation. Many of these 

efforts may require several months of design and construction, compounded by the fact that 

much of the work cannot be completed in cold-weather or heavy-rain seasons. 

1. Inflow Design Flood Controls for CCR Surface Impoundments and All Expansions

The Agency has concluded that the proposed requirement preventing run-on to a CCR 

surface impoundment was both impractical and unwarranted and could possibly disrupt effective 

storm water management systems operating at CCR facilities. Therefore, consistent with FEMA 

guidance, the Agency is modifying this requirement to require an owner or operator of an 

existing or new CCR surface impoundment or any lateral expansion to design, construct, operate, 

and maintain hydraulic and hydrologic capacity of CCR surface impoundments to: (1) 

adequately manage flow into the CCR surface impoundment during and following the peak 

discharge of the inflow design flood; and (2) adequately manage flow from the CCR unit to 

collect and control the peak discharge resulting from the inflow design flood. The inflow design 

flood is based on the Hazard Potential Classification of the unit as required by § 257.73 and § 

257.74 of this rule.111 The inflow design floods for specific hazard potential classifications are 

as follows: (1) the probable maximum flood (PMF) for high hazard potential CCR surface 

impoundments; (2) the 1000-year flood for significant hazard potential CCR surface 

 

111

 Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow Design Floods for Dams. 

August 1, 2013. FEMA P-94. 
Document submitted to conclude E.O.12866 Review

322

impoundments; (3) the 100-year flood for low hazard potential CCR surface impoundments; and 

(4) the 25-year flood for incised CCR surface impoundments.112 

EPA has based this revised language on the FEMA’s guidance entitled, “Selecting and 

Accommodating Inflow Design Floods for Dams,” which represents current and accepted 

practices in dam engineering and provides a consistent and uniform standard that has been 

adopted throughout dam engineering.

Incised CCR surface impoundments, as defined in this rule, are also required to meet 

inflow design flood requirements.113 While incised units do not pose the same potential for 

release as a diked unit, i.e., breach of dike and release of CCR, overtopping of an incised unit 

does represent a potential environmental hazard warranting control. EPA acknowledges, 

however, that overtopping of an incised unit would result in a release of CCR material through a 

surcharge flow, i.e., flow of a temporary stage overtopping the “crest” of the incised CCR 

surface impoundment, and would not precipitate the degradation of a dike and potential 

subsequent breach of a dike and massive release of contents of the CCR surface impoundment. 

To reflect the lower risks associated with such releases, and because incised CCR surface 

impoundments are not required to determine their hazard potential classification, the Agency is 

requiring that incised CCR surface impoundments only must accommodate a 25-year flood for 

the hydrologic and hydraulic capacity requirements of the rule. EPA chose the 25-year flood for 

incised CCR surface impoundments to maintain consistency with the proposed rule, which 

required that all units accommodate a 25-year storm event. As part of these requirements, EPA 

 

112

 All discharge from the CCR surface impoundment must be handled in accordance with the surface 

water requirements under § 257.3-3.

113

 Incised CCR surface impoundment means a CCR surface impoundment which is constructed by 

excavating entirely below the natural ground surface, holds an accumulation of CCR entirely below the 

adjacent natural ground surface, and does not consist of any constructed diked portion.
Document submitted to conclude E.O.12866 Review

323

is also finalizing a definition of inflow design flood and flood hydrograph. Inflow design flood 

has been defined to mean the flood hydrograph that is used to design or modify the CCR surface 

impoundment and its appurtenant works, and flood hydrograph has been defined to mean the 

temporal distribution of inflow into a CCR surface impoundment. 

2. Inflow Design Flood Control Systems

Controlling the inflow and outflow of the CCR surface impoundment reduces the risks of 

hydrologic failure, which include overtopping erosion, internal excessive seepage and piping, 

erosion of spillways, and overstressing of the structural components of the CCR surface 

impoundment. The CCR surface impoundment’s hydraulic and hydrologic capacity is to be 

designed based on the unit’s hazard potential classification as determined by a qualified 

professional engineer. To meet the performance standard in the rule, the CCR surface 

impoundment must be designed to have adequate hydraulic and hydrologic capacity to ensure 

that rainfall and watershed characteristics have been accounted for, the hydraulic ratings of all 

intake structures are adequate and free of obstruction, operating freeboard is adequate, all 

spillways and decant structures have adequate capacity, and all downstream hydraulic structures 

have adequate capacity. While not required, an antecedent flood study may be necessary to 

characterize the condition of the CCR surface impoundment under normal operating conditions.

EPA recognizes that in many impoundment configurations, an inflow design flood may 

be limited to the direct precipitation that falls within the perimeter of the CCR surface 

impoundment during a storm event, due to the lack of storm water inflow routing from adjacent 

catchment areas. Other CCR surface impoundments may have storm water or other hydrologic 

contributions from various catchment areas or other sources. The final rule’s hydraulic and 

hydrologic capacity standards require all CCR surface impoundments to have adequate hydraulic 
Document submitted to conclude E.O.12866 Review

324

and hydrologic capacity to accommodate all contributory inflow to CCR surface impoundments, 

regardless of the inflow’s origin. 

The hydraulic and hydrologic capacity requirements will minimize the potential for 

overtopping to occur from normal or abnormal operations, overfilling, wind and wave action, 

rainfall, and run-on, and will ensure that the unit is operated with appropriate consideration of 

these potentially adverse conditions. The Agency notes, however, that the operating freeboard of 

a CCR surface impoundment is subject to fluctuations, deviating from original design 

assumptions and specifications. Additionally, EPA notes that routine maintenance and alterations 

of hydraulic structures associated with the CCR surface impoundments, e.g., decant structures 

and spillways, can adversely impact the hydrologic and hydraulic capacity of the CCR surface 

impoundment. At no point should the inflow design flood exceed the capacity of the CCR 

surface impoundment, regardless of fluctuations in freeboard, maintenance of hydraulic 

structures, or other potential obstructions to the hydraulic and hydrologic capacity of the unit. 

The owner or operator must account for operational changes or diminished capacity in the 

calculation of hydraulic and hydrologic capacity of the CCR unit. 

3. Inflow Design Flood Control System Plan

The owner or operator of an existing CCR surface impoundment must prepare an initial 

inflow design flood control system plan to document that the design and construction of the 

system will achieve the rule’s performance standards no later than 18 months after the 

publication of this rule in the Federal Register. New CCR surface impoundments or lateral 

expansions of CCR surface impoundments must prepare an initial inflow design flood control 

system plan no later than the date of initial receipt of CCR in the unit. The owner or operator 

must obtain a certification from a qualified professional engineer that the plan meets all 
Document submitted to conclude E.O.12866 Review

325

applicable requirements of the rule for inflow design flood control system plans. The plan must 

also be supported by appropriate engineering calculations. This documentation should also 

include references, and drawings regarding the identification of the design storm for the 

catchment area affecting the CCR surface impoundment and the CCR surface impoundment 

itself, a characterization of the rainfall abstractions, including but not limited to depression 

storage and infiltration in the upstream catchment area affecting the CCR surface impoundment. 

In addition, EPA expects supporting documentation to address the selection and basis of an 

appropriate runoff model and an appropriate run-on or run-off routing model; the identification 

and characterization of any intake or decant structures of the CCR surface impoundment; an 

appropriate characterization of the spillway(s) of the CCR surface impoundment and their 

capacity; and characterization of downstream hydraulic structures which ultimately receive the 

discharge from the CCR surface impoundment. Finally, the owner or operator must comply with 

the recordkeeping, notification and internet requirements specified in the rule for the plan. 

The owner or operator may amend the written inflow design flood control system plan at 

any time prior to receipt of CCR in the CCR unit, during the operating life of the CCR unit, 

during closure of the CCR unit, or following closure of the CCR unit provided the revised plan is 

placed in the facility’s operating record. The owner or operator must amend the written inflow 

design flood control system plan whenever there is a change in the conditions that would 

substantially affect the written plan in effect. The owner or operator of the CCR surface 

impoundment must also periodically update the inflow design flood control system plan. The 

owner or operator must review or update an existing plan at a frequency no less than every five 

years. Changes in storm characteristics (e.g., intensity and duration) and upstream catchment 

area characteristics, hazard potential classifications, as well as build-out, operational changes, 
Document submitted to conclude E.O.12866 Review

326

and diminishing available capacity, all have the potential to influence inflow design flood 

volumes and therefore the effectiveness of the existing inflow design flood control systems. A 

periodic review of the plan to address these and other factors is necessary to ensure that the 

hydrologic and hydraulic capacity of the unit is maintained over time. An update of the inflow 

design flood control system plan should document any modifications pertinent to the inflow 

design flood control system. 

The owner or operator may amend the written inflow design flood control system plan at 

any time and must place the revised plan in the facility’s operating record. However, the owner 

or operator must amend the written inflow design flood control system plan whenever there is a 

change in the conditions that would substantially affect the written plan in effect. The owner or 

operator of the CCR unit must also review and, where necessary, update an inflow design flood 

control system plan every five years. As part of this review, the owner or operator must obtain

certification from a qualified professional engineer must certify that the inflow design flood 

control system plan, and any subsequent amendments continues to meet the requirements of the 

rule. The date of completion of the initial plan is the basis for establishing the deadline to 

complete the first subsequent plan. The owner or operator may complete any required plan prior 

to the required deadline, and must place the completed plan into the facility’s operating record 

within a reasonable amount of time. 

I. Operating Criteria – Inspection Requirements for CCR Surface Impoundments 

EPA proposed structural stability requirements for CCR surface impoundments based on 

the long-standing MSHA requirements, with only minor modifications. These structural stability 

requirements were covered in various sections of the proposed rule (see specifically proposed §§

257.71, 257.72, 257.83, and 257.84). Section 257.83 addressed requirements for periodic 
Document submitted to conclude E.O.12866 Review

327

inspections of CCR surface impoundments. In proposing these requirements, the Agency 

concluded that periodic inspections were critical to ensure that any problems relating to 

structural stability are quickly identified and remedied to prevent catastrophic releases, such as 

occurred at Martins Creek, Pennsylvania and TVA’s Kingston, Tennessee facility. The proposed 

rule required owners or operators to conduct: (1) weekly inspections to detect potentially 

hazardous conditions or structural weakness; and (2) annual inspections to assure that the design, 

operation, and maintenance of the surface impoundment was in accordance with generally 

accepted engineering standards. EPA proposed that weekly inspections be conducted by a 

person qualified to recognize specific signs of structural instability and other hazardous 

conditions by visual observation and, if applicable, to monitor instrumentation. The proposed 

rule also required annual inspection reports from an independent registered professional 

engineer, certifying that the design, operation, and maintenance of the CCR surface 

impoundment was in accordance with generally accepted engineering standards. Consistent with 

the annual inspection requirements, EPA, as part of its recordkeeping requirements also proposed 

that owners or operators of CCR surface impoundments annually document and report on, 

among other things: (1) changes in the geometry of the impounding structure; (2) location and 

type of instrumentation monitoring the unit; (3) the minimum, maximum and present depth and 

elevation of the impounded water, sediment or slurry for the reporting period; and (4) storage 

capacity of the impounding structure (see 75 FR at 35246).

The annual inspection provisions also required that if a potentially hazardous condition 

developed, the owner or operator must immediately take several actions: eliminate the 

potentially hazardous condition; notify potentially affected persons and state and local first 

responders; notify and prepare to evacuate, if necessary, all personnel from the property who 
Document submitted to conclude E.O.12866 Review

328

may be affected by the potentially hazardous condition(s); and direct a qualified person to 

monitor all instruments and examine the structure at least once every eight hours, or more often 

as required by an authorized representative of the state. Finally, the proposed rule required that 

inspection and monitoring reports be maintained in the facility operating record and placed on 

the facility’s publicly accessible internet site as well as promptly reporting the results of the 

inspection or monitoring to the state.

EPA specifically requested comment on whether to cover all CCR impoundments for 

stability (including the inspection requirements), regardless of height and storage volume, 

whether to use the cut-offs in the MSHA regulations, or whether other regulations, approaches, 

or size cut-offs should be used. The Agency further requested commenters who believed that 

other regulations or size cut-offs should be used (and not the size cut-offs established in the 

MSHA regulations) to provide the basis and technical support for their position. (75 FR 35176, 

35223). In response to EPA’s general solicitation for alternative size cut-offs, the Agency 

received little response. However, many commenters questioned EPA’s decision to require 

inspections for all CCR surface impoundments, given that the other structural stability 

requirements were triggered only if the CCR unit exceeded the proposed size threshold 

(consistent with MSHA requirements). Commenters argued that there was no basis to require 

inspections of all CCR surface impoundments given that units below the specified size threshold 

had a much lower risk of catastrophic failure. A more limited requirement the commenter’s 

argued, was supported by MSHA’s decision to regulate only those “larger” sized units. Other 

commenters argued that inspection timeframes should take into account site specific conditions 

at the site and be based on the recommendations of an independent, registered, professional 

engineer. Commenters reasoned that while, in theory, a short inspection interval (i.e., a weekly 
Document submitted to conclude E.O.12866 Review

329

inspection) should increase the chances of finding an adverse condition, the judgment of a 

qualified professional engineer to establish the frequency and focus, as well as the purpose of the 

dam safety inspection was a far more effective method for detecting and preventing the 

development of a potentially adverse situation. Still other commenters questioned the overall 

value of a weekly inspection if, as proposed, no documentation of the results was required.

In reviewing the proposed regulatory language, it appears an error was made. Although 

the preamble generally stated that the proposed regulatory requirements addressing stability 

(which included inspections) applied only to those CCR surface impoundments exceeding the 

specified size threshold established by the MSHA regulations, the regulatory text required 

inspections for all CCR units. The final rule requires weekly general inspections and monthly 

instrumentation inspections to be conducted for all CCR surface impoundments. Periodic 

inspections of all CCR units are a necessary practice to ensure that the overall structural integrity 

of the CCR unit is maintained and that actual and potential structural weaknesses and other 

hazardous conditions are quickly identified and remediated throughout the active life of the unit. 

All CCR surface impoundments pose some risk of release—whether from a catastrophic failure 

or from a more limited structural failure, such as occurred at Duke Energy’s Dan River plant. 

Periodic inspections are a generally accepted, prudent engineering practice that will significantly 

reduce the risks of such failures; during the Impoundment Assessment Program, EPA discovered 

that many facilities routinely conduct some sort of periodic inspection and monitoring, although 

the frequency varied widely between facilities. The final rule merely codifies this practice, by 

establishing a consistent minimum timeframe. EPA is therefore requiring that all CCR surface 

impoundments be inspected by a qualified person both weekly (for visual signs of a potentially 

adverse condition) and monthly (for instrumentation monitoring). Consistent with the proposed 
Document submitted to conclude E.O.12866 Review

330

rule, EPA is also requiring annual inspections for all CCR surface impoundments that exceed the 

specified size threshold of: (1) a height of five feet and a storage capacity of 20 acre-feet; or (2) a 

height of 20 feet, must also be inspected no less than annually by a qualified professional 

engineer. These inspection requirements are generally being promulgated as proposed, with 

minor technical clarifications. 

The final inspection requirements have been drawn heavily from guidelines established 

by FEMA for dam safety, under which maintaining structural integrity involves continuous 

evaluation of the unit, based on periodic inspections. To be most effective, FEMA suggests, and 

EPA concurs, that inspections be varied with respect to both the time interval between 

inspections and the level of detail of the inspection. FEMA guidance, in part, suggests that 

inspections can be categorized as either: visual observations to identify abnormal conditions (i.e., 

informal inspections); field inspections by a professional engineer (i.e., intermediate 

inspections); and a technical review to determine if the unit meets current and accepted design 

criteria and practices (i.e., formal inspection). 114 In general, FEMA recommends that 

inspections focusing on visual observations should be conducted often (e.g., weekly) while more 

substantive technical evaluation should be conducted every year to every five years depending 

on the engineering analyses required. (See also the preamble discussion on the requirements 

specified in §§ 257.73 and 257.74 of this rule, in particular the discussion addressing the five 

year time interval for structural stability and factor of safety reassessments.) 

For the reasons discussed above, EPA has concluded, consistent with FEMA guidelines, 

that routine inspections of all CCR units are necessary to ensure that the units are safely operated 

 

114 See “Federal Guidelines for Dam Safety” Federal Emergency Management Agency. (Reprinted April 

2004).
Document submitted to conclude E.O.12866 Review

331

and that issues that could disrupt the safety and continuing operation of these units are promptly 

identified and remediated. Accordingly, the final rule requires both weekly inspections and 

monthly instrumentation inspections to be conducted at all CCR surface impoundments to 

confirm that they are operating safely. These inspections must be conducted by a qualified 

person trained to recognize specific signs of structural instability and other hazardous conditions 

by visual observation and if, applicable monitor instrumentation. EPA is also retaining the 

annual inspection requirement for CCR surface impoundments exceeding the specified size 

threshold established in this rule. This inspection must be conducted and certified by a qualified 

professional engineer. Units exceeding this size threshold pose a higher degree of risk of release 

of CCR to the environment than other types of CCR surface impoundments (e.g., incised or 

“small” CCR units) and as such warrant additional regulatory control and oversight. 

The final rule for requires that both weekly inspections of the CCR unit and monthly 

monitoring of CCR unit instrumentation be initiated within 6 months of the effective date of the 

rule.

Within 9 months of the effective date of the rule, the owner or operator must complete 

the initial annual inspection of the CCR unit. Initial annual inspection requires the retaining of a 

professional engineer along with the familiarization of the engineer with the facility and CCR 

units. Additionally, the annual inspection should not be conducted unless weekly inspection and 

monthly instrumentation monitoring has been initiated and established in order to generate a 

body of information for the professional engineer to consider. Furthermore, in some coldweather regions of the United States, weather may inhibit adequate inspection of CCR units, 

whether through snow or ice cover. EPA is establishing a timeframe of 9 months after the 

effective date of the rule so as to allow for adequate weather conditions for inspection.
Document submitted to conclude E.O.12866 Review

332

1. Surface Impoundment Inspection Requirements

a. Weekly Inspections

As presented in the proposed rule and finalized here, this rule requires all CCR surface 

impoundments to be examined by a qualified person at least once every seven days for any 

appearance of actual or potential structural weakness or other conditions that are disrupting or 

that have the potential to disrupt the operation or safety of the CCR unit. The results of the 

inspection by a qualified person must be recorded in the facility’s operating record.

Weekly inspections are intended to detect, as early as practicable, signs of distress in a 

CCR surface impoundment that may result in larger, more severe conditions. They are also 

designed to identify potential issues with hydraulic structures that may affect the structural safety 

of the CCR surface impoundment and impact the hydraulic and hydrologic capacity of the CCR 

surface impoundment. The early detection of signs of structural weaknesses is an essential 

preventative measure which helps to impede structural failure. The required weekly inspections 

are designed identify such signs of structural weakness before they develop into larger, 

debilitating concerns in the structural stability of the dike.

Appearances of structural weakness may include, but are not limited to: (1), excessive, 

turbid, or sediment- laden seepage; (2) signs of piping and other internal erosion; (3) transverse, 

longitudinal, and desiccation cracking; (4) slides, bulges, boils, sloughs, scarps, sinkholes, or 

depressions: (5) abnormally high or low pool levels; (6) animal burrows; (7) excessive or lacking 

vegetative cover; (8) slope erosion; and (9) debris. 

In addition, EPA is also adopting a new provision that requires the qualified person to 

inspect the discharge of all outlets of hydraulic structures which pass underneath the base of the 

CCR surface impoundment or through the dike of the CCR unit for abnormal discoloration, flow, 
Document submitted to conclude E.O.12866 Review

333

or discharge of debris or sediment. The requirement is being added to aid in the identification of 

any internal or sub-surface issues which cannot be reasonably identified in a routine visual 

inspection. Abnormal discharges from hydraulic structures are often an indication of potential 

issues with the sub-surface or internal integrity of the structure. Hydraulic structures, particularly 

corrugated metal pipe, are subject to deterioration and corrosion over time and, as deterioration 

proceeds, the hydraulic structure becomes more susceptible to collapse, translation, or 

malfunction. Issues with hydraulic structures within the dike may exacerbate structural or 

operational issues with the CCR surface impoundment due to the significant internal 

deterioration of the dike via the hydraulic structure. As an example, on February 2, 2014, Duke 

Energy’s Dan River Fossil Plant experienced a structural collapse of a corrugated metal storm 

water discharge pipe which passed underneath the interior of a CCR surface impoundment. The 

subsequent collapse of the base of the CCR surface impoundment led to a massive release of 

CCR to the environment. Additionally, the adjacent dike of the CCR surface impoundment was 

severely damaged due to the erosion of the upstream slope.

Further, an owner or operator may want to consider inspections outside of the weekly, 

seven-day schedule if an unanticipated event, such as a flood, earthquake, or vandalism occurs 

on the site. While rare in occurrence, these events may increase the chances that a potential 

structural stability issue has arisen. Prudent CCR management practices dictate that a visual 

assessment is warranted after such events. For example, after a large flood (considered a flood 

with a return period of equal or greater frequency of ten years) there is potential for damage, 

including structural damage to the CCR surface impoundment, caused by increased reservoir 

levels that inundate areas infrequently inundated. The slopes of the dike should be inspected to 

ensure that no significant erosion has occurred due to the flood, or that any large debris or 
Document submitted to conclude E.O.12866 Review

334

sediment has been deposited on the dike. An inspection should also be conducted following an 

earthquake where earthquake damage is observed or can be reasonably expected, where ground 

motion is felt at the CCR surface impoundment or in nearby locations, or following established 

magnitude-epicenter distance relationships.115

b. Monthly Instrumentation Inspection 

In a departure from the proposed rule, EPA is requiring the monitoring of all 

instrumentation supporting the operation of the CCR unit to be conducted by a qualified person 

no less than once per month. This is a change from the proposal which required instrumentation 

to be monitored no less than every seven days. 

Many commenters argued that requiring inspections every seven days was excessive, 

and that, based on FEMA guidelines for dam safety, a more reasonable timeframe would be once 

per month for CCR surface impoundments with a hazard potential rating of "high" and quarterly 

for those CCR surface impoundments with a hazard potential rating of "significant." In 

considering these comments, the Agency was influenced by a number of factors including the 

FEMA guidelines suggested by the commenters. Also weighing heavily in EPA’s decision were 

the observations made as part of the Assessment Program, which revealed that many CCR units 

are equipped with only “basic” measuring devices such as piezometers and pool elevation and 

freeboard instrumentation and not the more sophisticated (i.e., sensitive) measuring devices for 

measuring pressure, seepage, internal movement, slope movement; and vibration. These 

findings strongly suggested to the Agency that, given the status of current instrumentation 

 

115

 The US Army Corps of Engineers have developed useful criteria for post-earthquake inspections, 

specifically their published magnitude-epicenter distance criteria in Table 11.1 of “Safety of Dams –

Policy and Procedures,” ER 1110-2-1156, 31 March 2014115. The criteria stipulate when the dam (or in 

the case of this rule, CCR surface impoundment) should be inspected.
Document submitted to conclude E.O.12866 Review

335

employed at CCR facilities, weekly monitoring would be excessive, impractical, and—of 

greatest significance--unlikely to indicate any measurable changes in structural stability in such a 

short time frame. EPA, therefore, agrees that a monthly time frame is a more appropriate 

interval for detecting discernible or significant changes in the operation of the CCR unit. EPA 

has not, however, differentiated between high, significant, and low hazard potential CCR surface 

impoundments in the requirement that instrumentation be monitored monthly, as commenters 

suggested. Through the Assessment effort, EPA identified that typically low hazard potential 

CCR surface impoundments were monitored less frequently than high- or significant hazard 

potential CCR surface impoundments by the owner or operator. Additionally, these low hazard 

potential CCR surface impoundments less commonly were equipped with sophisticated 

monitoring instrumentation, including remote monitoring instrumentation which would allow the 

owner or operator to monitor the unit from a remote location. Based on these observations, along 

with the limited burden that instrumentation monitoring places on the owner or operator, the rule 

requires all CCR surface impoundments with instrumentation to be monitored monthly. 

c. Annual Inspections

The rule requires owners or operators of any CCR surface impoundments exceeding the 

MSHA size threshold (i.e., a height of five feet or more and a storage volume of 20 acre-feet or 

more; or a height of 20 feet or more) to conduct annual inspections of the CCR unit throughout 

its operating life. These annual inspections are focused primarily on the structural stability of the 

CCR surface impoundment and must ensure that the operation and maintenance of the CCR 

surface impoundment is in accordance with recognized and generally accepted good engineering 
Document submitted to conclude E.O.12866 Review

336

standards. Inspections must be conducted and certified by a qualified professional engineer.116 

Incised CCR surface impoundments, as defined in § 257.53 are not subject to the annual 

inspection requirements. Incised units present lower risks of structural failure, and so weekly 

inspections are sufficient to address any risks associated with these CCR units.

Annual inspections of any CCR surface impoundment must include, at a minimum: (1) a 

review of all previously generated information regarding the status and condition of the CCR 

unit, including, but not limited to, all operating records and publicly accessible internet site 

entries, design and construction drawings and other documentation; (2) a thorough visual 

inspection to identify indications of distress, unusual or adverse behavior, or malfunction of the 

CCR unit and appurtenant structures; and (3) a thorough visual inspection of hydraulic structures 

underlying the base of the CCR unit and passing through the dike of the CCR unit for structural 

integrity and continued safe and reliable operation. Additionally, following each inspection, the 

qualified professional engineer must prepare an inspection report which documents the 

following: (1) any changes in geometry of the impounding structure since the previous annual 

inspection; (2) the location and type of existing instrumentation and the maximum recorded 

readings of each instrument since the previous annual inspection; (3) the approximate minimum,

maximum, and present depth and elevation of the impounded water and CCR since the previous 

annual inspection; (4) the storage capacity of the impounding structure at the time of inspection; 

(5) the approximate volume of the impounded water and CCR at the time of the inspection; and 

(6) any appearances of an actual or potential structural weakness of the CCR unit, in addition to 

any existing conditions that are disrupting or have the potential to disrupt the operation and 

 

116

 For purposed of this requirement, qualified means an individual experienced in the operation and 

maintenance of dams and who has been trained to recognize signs of concern and structural weakness by 

visual observation, and if applicable, to monitor instrumentation.
Document submitted to conclude E.O.12866 Review

337

safety of the CCR unit and appurtenant structures; and (7) any other change(s) which may have 

affected the stability or operation of the impounding structure since the previous annual 

inspection.

This last set of requirements was originally presented in § 257.84 of the proposed rule 

(i.e., recordkeeping requirements), however, the Agency has moved these requirements to the 

annual inspection section of the rule because (1) these requirements apply only to CCR surface 

impoundment exceeding the specified size threshold, rather than all CCR surface impoundments, 

as proposed; (2) must be reported annually; and (3) are more appropriately housed in the 

inspection section.

The owner or operator of existing CCR surface impoundments must ensure that the initial 

annual inspection by a qualified professional engineer is completed and documented with a 

report no later than three months after the effective date of the rule. EPA established this 

timeframe for completing an initial annual inspection based on its experience with the 

Assessment Program. In an effort similar to conducting an initial annual inspection, the 

following tasks were generally completed within three months: retaining the services of a 

qualified professional engineer, developing a scope of work, reviewing existing documentation on the 

CCR unit, conducting a thorough field inspection, and completing an inspection report Owners 

and operators of new CCR surface impoundment must commence annual inspections no later 

than one year from the initial placement of CCR into the new unit. An annual inspection is not 

required in any calendar year in which the five year structural stability reassessment is also 

required to be completed. (See §§ 257.73 and 257.74.) The report which the qualified 

professional engineer has documented must be placed in the facility’s operating record and 

placed on the facility’s publicly accessible internet site. An annual inspection is considered 
Document submitted to conclude E.O.12866 Review

338

complete when the inspection report has been placed in the facility’s operating record. Finally, if 

a deficiency is identified during an inspection, the owner or operator must take immediate 

measures to remedy the structural weakness or disrupting condition as soon as feasible.

J. Operating Criteria - Inspections for CCR Landfills 

Under RCRA Subtitle D Parts 258, EPA does not require specific inspection 

requirements for MSWLFs. Rather, EPA relies on states to establish their own inspection criteria 

and frequency of inspections to ensure protection of human health and the environment. It is the 

Agency’s understanding that many states require owner/operators of MSWLFs to conduct either 

daily, weekly, quarterly and annual inspections of these units to ensure that the design, 

construction, operation, and maintenance complies with all requirements. In addition, based on a 

review of selected state regulations most states conduct state inspections of operating landfills no 

less than annually.

Under the proposed subtitle D option, EPA did not propose to require mandatory 

inspections of new or existing landfills or any lateral expansion. However, under the subtitle C 

option, EPA proposed to apply the requirements of §264.303 to permitted CCR landfills. 

Specifically, these requirements stated that CCR landfills while in operation would be required to 

be inspected weekly and after storms to detect evidence of any of the following: (1) 

deterioration, malfunctions, or improper operation of run on and run-off control systems; (2) 

proper functioning of wind dispersal control systems, where present; and (3) the presence of 

leachate in and proper functioning of the leachate collection and removal system where present. 

(See proposed §264.1306, 75 FR 35257). 

Upon further evaluation, the Agency has decided, consistent with the weekly inspection 

requirements proposed for CCR landfills under the subtitle C option, as well as many state 
Document submitted to conclude E.O.12866 Review

339

requirements for MSWLFs, to require all existing and new CCR landfills and any lateral 

expansion to conduct, at intervals not exceeding seven days, inspections by a qualified person for 

any appearances of actual or potential structural weakness or any other conditions which are 

disrupting or have the potential to disrupt the operation or safety of the CCR landfill. In addition, 

EPA is also requiring inspections by a qualified professional engineer at intervals not exceeding 

one year to ensure that the design, construction, operation, and maintenance of the CCR landfill 

is consistent with recognized and generally accepted good engineering standards. This 

inspection must include a review of all data in the operating record as well as a visual inspection 

of the unit to identify signs of distress or malfunction that is or potentially could affect the safe 

operation of the unit. The qualified professional engineer must then also prepare a report to 

identify and discuss the findings of the inspection as well as a discussion of potential remedies 

for addressing any deficiencies discovered during the inspection. The Agency has concluded 

that all CCR landfills should be routinely inspected to ensure that they are operating as designed 

and are being maintained in compliance with the federal criteria.

The Agency is promulgating these inspection requirements based on: (1) a review of state 

municipal landfill inspection requirements; and (2) comments from parties that clearly supported 

inspections of all CCR landfills. The Agency reviewed MSWLF inspection checklists in a 

selected number of states to assess the scope of these inspections. The Agency also conducted a 

preliminary review of state MSWLF regulations for New York, Pennsylvania, Ohio, Wisconsin, 

Illinois, Missouri, North Dakota and California. All of these states require municipal landfill 

owner/operators to conduct a either daily, weekly, monthly, quarterly and annual inspections 

addressing the following: (1) proper placement of the waste; (2) landfill slopes are stable and that 

erosion is controlled: (3) surface water percolation is minimized (i.e. reduce ponding): (4) liner 
Document submitted to conclude E.O.12866 Review

340

systems and leachate collection systems are properly operated and maintained: (5) water quality 

monitoring systems are maintained and operating; (6) dust is controlled; and (7) a plan is in place 

to promptly address and correct problems and deficiencies discovered during the inspection. The 

Agency also noted during its review of state regulations that states reserve the right to inspect 

landfills at any time and routine conduct state inspections on a no less than annual basis. CCR 

landfills present at least the same level of risks as MSWLFs, and while the operations may differ, 

both operating systems are equally susceptible to malfunction. Weekly inspections of all CCR 

landfills by a qualified person are therefore equally necessary to ensure that ground water 

monitoring, run-on/runoff controls, liner systems, and leachate collection systems are operated 

and maintained to reduce adverse environmental and human health impacts. 

This rule also requires that all existing and new CCR landfills and any lateral expansion 

conduct an annual inspection by a qualified professional engineer to assure that these units are 

designed, constructed, operated, and maintained throughout their operating life to ensure 

protection of human health and the environment. The Agency finds that annual inspections for 

these units are justified for the following reasons: (1) CCR landfills are large engineered units 

that require, that a variety of design and operating parameters be assessed to assure that the CCR 

landfill is operating as designed. Of particular concern to the Agency is the fact that coal ash is a 

fine grained material that may have the potential to compact and clog leachate collection systems 

(see: “Operations and Maintenance Guidelines for Coal Ash Landfills” Christopher Hardin, et. 

al. 2011 World of Coal Ash Conference. May 2011). It is reasonable therefore that the rule 

requires annual inspections to assure that these liner and leachate systems are assessed to assure 

that they are performing their functions as designed. (2) A formal annual inspection would 

review data collected during weekly inspections and determine if any remedial actions are need 
Document submitted to conclude E.O.12866 Review

341

to address deficiencies, (3) the annual review by a qualified professional engineer ensures that a 

detailed level of engineering analysis of operating conditions are evaluated which could lead to 

recommendations to address design or operating issues that need attention. 

K. Groundwater Monitoring and Corrective Action

EPA is finalizing groundwater monitoring and corrective action requirements to ensure 

that groundwater contamination at new and existing CCR disposal units will be detected and 

cleaned up as necessary to protect human health and the environment. These requirements 

reflect Congressional intent that protection of groundwater be a prime objective of any new solid 

waste regulations. As stated in the proposal, EPA's damage cases and risk assessments indicate 

there is significant potential for CCR landfills and CCR surface impoundments to leach 

hazardous constituents into groundwater, impair drinking water supplies and cause adverse

impacts on human health and the environment. Indeed, groundwater contamination is one of the 

key environmental and human health risks EPA has identified with CCR landfills and CCR 

surface impoundments. Groundwater monitoring is a key mechanism for facilities to verify that 

the existing containment structures, such as liners and leachate collection and removal systems, 

are functioning as intended. Thus, in order for a CCR landfill or CCR surface impoundment to 

show no reasonable probability of adverse effects on health or the environment, a system of 

routine groundwater monitoring to detect any contamination from a CCR disposal unit, and 

corrective action requirements to address identified contamination, are essential.

EPA proposed to require that a system of monitoring wells be installed at all new and 

existing CCR units. The regulation would also provide procedures for sampling these wells and 

methods for statistical analysis of the analytical data derived from the well samples to detect the 

presence of hazardous constituents released from these CCR disposal units. The Agency 
Document submitted to conclude E.O.12866 Review

342

proposed a groundwater monitoring program consisting of detection monitoring and assessment 

monitoring, and a corrective action program. This phased approach to groundwater monitoring 

and corrective action programs provides for a graduated response over time to the problem of 

groundwater contamination as the evidence of such contamination increases. This allows for 

proper consideration of the transport characteristics of CCR constituents in ground water, while 

protecting human health and the environment.

EPA largely based these proposed groundwater monitoring requirements on those for 

MSWLFs in the 40 CFR part 258 criteria, albeit with certain modifications to tailor the 

requirements to the case at hand. In particular, the possibility that a state may lack a permit 

program for CCR disposal units made it impossible to include some of the alternatives available 

in 40 CFR part 258, which establish alternative standards that allow a state, as part of its permit 

program to tailor the default requirements to account for site specific conditions at the individual 

facility. EPA also sought to tailor the proposed requirements for CCR units, by incorporating 

certain provisions from the interim status regulations, which operate in the absence of a permit, 

and by including in several of the proposed requirements, a certification by an independent 

registered professional engineer that the rule’s requirements had been met. 

In the proposed rule, the Agency required facilities to install a groundwater monitoring 

system that met a specified performance standard and that consisted of a minimum of one 

upgradient and three downgradient wells at all CCR disposal units. EPA acknowledged in the 

proposal that the design of an appropriate groundwater monitoring system is particularly 

dependent on site conditions relating to groundwater flow, and on the development of a system 

that has a sufficient number of wells, installed at appropriate locations and depths, to yield 

groundwater samples from the uppermost aquifer that represents the quality of background 
Document submitted to conclude E.O.12866 Review

343

groundwater that has not been affected by contaminants from a CCR unit. EPA's existing 

requirements under 40 CFR parts 258 and 264 recognize this, and because they operate in a 

permitting context, these requirements provide more flexibility in establishing groundwater 

monitoring systems. But because the same guarantee of permit oversight is not available under 

the criteria developed for the proposal, EPA proposed to establish a minimum requirement based 

on the part 265 interim status regulations, which are self-implementing. Long experience 

demonstrates that these monitoring requirements will be protective of a wide variety of 

conditions and wastes, and that facilities can feasibly implement these requirements. EPA also 

noted that in many instances a more detailed groundwater monitoring system will need to be in 

place, and EPA therefore proposed requiring a certification by the independent registered 

professional engineer that the groundwater monitoring system is designed to detect all significant 

groundwater contamination.

EPA also proposed to require that owners and operators of CCR disposal units establish

consistent sampling and analysis procedures to determine whether a statistically significant 

increase in the level of a hazardous constituent(s) has occurred, indicating the presence of 

groundwater contamination.

As noted, EPA proposed a phased approach to monitoring. The first phase is detection 

monitoring where indicators would be monitored to determine whether groundwater was 

potentially being contaminated. The parameters EPA proposed to be used as indicators of 

groundwater contamination were the following: boron, chloride, conductivity, fluoride, pH, 

sulfate, sulfide, and total dissolved solids (TDS). In selecting the parameters for detection 

monitoring, EPA chose constituents that are present in CCR and would rapidly move through the 

subsurface, and thus provide an early detection of whether contaminants were migrating from the 
Document submitted to conclude E.O.12866 Review

344

CCR disposal unit. Under the proposed rule, monitoring would be required no less frequently 

than semiannually. 

When a statistically significant increase over background levels is detected for any of 

these parameters, the proposed rule would require the facility to begin an assessment monitoring 

program to determine if releases of CCR constituents of concern had occurred. The parameters 

that were proposed for assessment monitoring included aluminum, antimony, arsenic, barium, 

beryllium, boron, cadmium, chloride, chromium, copper, fluoride, iron, lead, manganese, 

mercury, molybdenum, pH, selenium, sulfate, sulfide, thallium, and total dissolved solids.

The proposed rule also required that whenever monitoring results indicate a statistically 

significant level exceeding the groundwater protection standard for any of these parameters, the 

owner or operator must start the process for cleaning up the contamination, and initiate an 

assessment of corrective action remedies. The proposed rule required that the assessment of 

correction action remedies be initiated within 90 days and then completed within 90 days.

EPA proposed that the assessment of corrective measures must consider a number of 

factors, including the effectiveness, performance, and time needed for the potential remedies. As 

part of the assessment of corrective measures, the owner or operator was required to identify the 

source of the release. The owner or operator was also required to gather data on plume 

definition, fate of the contaminants, stratigraphy and hydraulic properties of the aquifer. The 

owner or operator also was required to consider whether immediate measures to limit further 

plume migration or measures to minimize further introduction of contaminants to groundwater 

would be necessary. EPA also proposed to require the owner or operator to provide notification 

of the corrective measures assessment to the State Director, place the corrective measures 

assessment in the operating record and on the owner’s or operator’s publicly accessible internet 
Document submitted to conclude E.O.12866 Review

345

site, and discuss the results of the corrective measures assessment in a public meeting with 

interested and affected parties.

Based on the results of the corrective measures assessment, EPA proposed to require the 

owner or operator to select a remedy based on a number of factors, including: the long- and 

short-term effectiveness and protectiveness of the potential remedy, along with the degree of 

certainty that the remedy will prove successful; the effectiveness of the remedy in controlling the 

source to reduce further releases; the ease or difficulty of implementing a potential remedy; the 

degree to which community concerns are addressed by a potential remedy; and potential risks to 

human health and the environment from exposure to contamination prior to completion of the 

remedy. The owner or operator was also required to specify as part of the selected remedy a 

schedule for initiating and completing remedial activities.

Under the proposed rule, implementing the corrective action program would require the 

owner or operator to establish and implement a corrective action groundwater monitoring 

program; implement the corrective action remedy selected; and take any interim measures 

necessary to ensure the protection of human health and the environment, all according to the 

schedule the owner or operator developed during the assessment of corrective measures.

The proposed rule also required that the owner or operator must demonstrate that 

concentrations of constituents have not exceeded the ground water protection standards for three 

consecutive years in order to support a determination that the remedy is complete.

The majority of the commenters supported “appropriate groundwater monitoring 

standards for CCR waste management units” and the development of such standards under a 

RCRA subtitle D framework. Comments were received on various parts of the groundwater 

monitoring scheme laid out in the proposed rule. The majority of comments received requested 
Document submitted to conclude E.O.12866 Review

346

EPA to provide “more flexibility” to the proposed requirements. Many commenters wanted the 

states to be more involved with the process and provided comments suggesting that additional

“flexibility,” such as is provided in the 40 CFR part 258 regulations for MSWLFs as part of the 

permitting process, be extended to CCR units. For example, commenters wanted states to have 

the authority to add or drop monitoring constituents; approve alternatives to schedules; modify 

the number of wells needed; allow variances; allow alternatives to the point of compliance

specified in the rule; employ alternative methods to detect potential groundwater contamination, 

such as leak detection systems; allow alternatives to the statistical methods used to determine 

whether groundwater contamination has occurred; and to replace the qualified professional 

engineer role in the certification process. 

For the final rule, EPA has developed a groundwater monitoring program that is flexible 

and allows facilities to design a system that accounts for site specific conditions within specific 

parameters. The final rule establishes an overall performance standard that the system must 

meet, lays out the minimum requirements of an effective system, and requires the owner or 

operator to design a system that achieves that overall performance standard based on a full 

characterization of site conditions. 

As described in more detail below, in certain cases, EPA was able to develop 

performance standards to serve as “more flexible” alternatives to the technical specifications laid 

out in the proposal. In these instances, the available information allowed the Agency to develop 

performance standards that were sufficiently objective and determinate that EPA could conclude 

that the 4004(a) standard would be met nationwide. 

However, many of the commenters’ requests related to alternatives that would be less 

stringent than the minimum criteria laid out in the proposal and were based on arguments that 
Document submitted to conclude E.O.12866 Review

347

state regulators (or facilities) should be allowed to “tailor” those requirements to sites that did 

not need those particular requirements. As explained at length in the proposal, EPA is concerned 

that provisions allowing such modifications are particularly susceptible to abuse, since in many 

cases the provisions could allow substantial cost avoidance. In the absence of a mandated state 

oversight mechanism to ensure that the suggested modifications are technically appropriate, 

these kinds of provisions can operate at the expense of protectiveness. In Unit II of this

preamble, EPA explains the extent of our authority to establish criteria under RCRA sections 

1008(a)(3) and 4004(a), including the implications associated with the lack of any authority to 

establish a program analogous to part 258, which relies on approved states to implement the 

Federal criteria through a permitting program. As a result of the statutory structure, this rule is 

self-implementing and is designed to operate to ensure that facilities will manage CCR in a 

manner that achieves the 4004(a) standard even in the absence of any regulatory entity available 

to judge the reasonableness of the desired alternatives. While some states currently do have 

programs for the regulation of CCR, which in some cases may be more stringent than this final 

rule, the federal program must be defensible on the record in place at the time the final rule is 

adopted. Based on the current rulemaking record, in most cases EPA lacked the information 

necessary to defend the commenters’ less stringent alternatives (i.e., the commenters’ requested 

“flexibilities”) to the minimum technical criteria specified in this rule for these units. Under both 

the subtitle C and part 258 programs, EPA can rely on subsequent proceedings to develop the 

information necessary to support such tailoring. This is clearly neither contemplated nor 

authorized under the regulatory program relevant to this rule. 

In addition, given the extremely technical nature of these requirements, EPA remains 

concerned that such provisions would render the requirements appreciably more difficult for 
Document submitted to conclude E.O.12866 Review

348

citizens to effectively enforce. Nevertheless, working within these constraints this rule 

specifically allows the PE to design a system that accounts for site conditions within the 

parameters of the minimum technical criteria, and EPA has added language to the regulation that 

expressly clarifies this. Moreover, states that have programs can continue to impose more 

stringent requirements, and thus can require, for example, additional monitoring wells, 

monitoring of additional aquifers, and inclusion of additional parameters to the detection 

monitoring list or the assessment monitoring list. The following discussion addresses in more 

detail the technical requirements under groundwater monitoring and corrective action in the final 

rule.

1. Applicability

Consistent with the provisions in the proposed rule, the final rule requires a system of 

monitoring wells to be installed at all CCR landfills, CCR surface impoundments and lateral 

expansions. Existing CCR units must install the groundwater monitoring system, develop their 

groundwater sampling and analysis procedures, develop background levels for Appendix III and 

Appendix IV constituents, and begin detection monitoring (§ 257.90 through § 257.94) within 

two years of the effective date of this rule. The proposed rule required that existing CCR units 

comply with the groundwater monitoring requirements within one year of the effective date. 

EPA proposed one year believing that it would be feasible for facilities to install the necessary 

systems. EPA also believed that a one year timeframe would ensure that existing CCR disposal 

facilities begin monitoring groundwater as soon as possible, so that releases from existing CCR 

disposal units are detected and addressed. Comments received on this issue argued that the oneyear timeframe was not sufficient to complete a hydrogeologic study and develop a monitoring 

plan. Several commenters requesting more time mentioned staffing shortages and limited 
Document submitted to conclude E.O.12866 Review

349

contractor and lab resources. One state, referencing its experience relating to development and 

implementation of groundwater monitoring systems, said that a one year timeframe to 

investigate, design and submit and obtain approval for the installation of an effective 

groundwater monitoring system was unreasonable. Most commenters thought that a timeframe 

of two years was reasonable. After review of the comments received on this issue and careful 

reexamination of the actual requirements in the final rule, EPA agrees that a one-year timeframe

is not feasible, and has decided to extend the timeframes for completing installation of the 

system, including background monitoring, to two years. As important as it is to begin detecting 

and addressing releases to groundwater, it is equally important that these complex systems be 

designed and installed correctly. That generally entails a number of activities, many of which 

must occur sequentially, including: determining the uppermost aquifer, deciding whether to 

install a single or multi-unit monitoring system, collecting and evaluating hydrogeological 

information that can be used to model the site, characterizing the site geology, characterizing the 

groundwater flow beneath the site, determining the flow direction and hydraulic gradient, 

establishing horizontal and vertical flow direction, determining hydraulic conductivity, 

determining groundwater flow rate, determining the monitoring wells placement, selecting the 

drilling method, designing the monitoring wells, developing sampling and analysis procedures, 

choosing a statistical method for evaluating the data and beginning detection monitoring. We 

also recognize that in some states, the state may require the owner or operator to receive state 

approval before they can install a groundwater monitoring system. Two years is a more 

reasonable timeframe in which to carry out these activities. New CCR landfills, new CCR 

surface impoundments and any new lateral expansion must comply with these same requirements 

(§§ 257.90 through 257.94) before any CCR can be placed in the CCR unit.
Document submitted to conclude E.O.12866 Review

350

Consistent with the proposal, the final rule also requires that the owner or operator of the 

CCR facility annually certify that each CCR unit is in compliance with the groundwater 

monitoring and corrective action provisions and provide a copy of this certification to the State 

Director. Because this is a self-implementing rule that relies on citizen enforcement, it is 

important for the owner or operator of the facility to periodically document that they are in 

compliance with the existing groundwater monitoring requirements, and an annual certification 

is the easiest and most effective way to achieve this. While the groundwater monitoring data will 

be made available on the owner or operator’s publicly accessible website and in the operating 

record of the facility, the analysis of these data is complicated and requires a certain level of 

scientific expertise to analyze the data correctly. As such, a document that serves as both an 

interpretative record of scientific analysis and regulatory compliance is critically important to the 

successful implementation of a self-implementing rule that is to be enforced exclusively by 

citizens and the states. For similar reasons, the certification must also be placed in the operating 

record, provided to the State Director, and posted on the owner or operator’s publicly accessible 

website. 

The groundwater monitoring requirements must be met throughout the active life of the 

disposal unit, as well as during the closure and post-closure care period of the CCR unit. 

EPA has added a new provision to § 257.90 to address the corrective action requirements 

that apply when CCR have been released into the environment, such as from the kind of 

structural failure that occurred with TVA’s Kingston Fossil Fuel plant release, or from the kind 

of release that occurred in North Carolina at the Dan River. EPA inadvertently drafted the 

corrective action requirements in the proposed rule to apply exclusively upon detection of 

groundwater contamination caused by a leaking unit. However, there is no reason to establish 
Document submitted to conclude E.O.12866 Review

351

different corrective action provisions for conducting clean-up operations for different kinds of 

releases; the same general process is applicable to all kinds of releases. 

The new provision requires that in the event of a release from a CCR unit, the owner or 

operator must immediately take all necessary measures to control the source(s) of releases so as 

to reduce or eliminate, to the maximum extent practicable, further releases of contaminants into 

the environment. The owner or operator of the CCR unit is also required to comply with all of 

the relevant corrective action requirements in §§ 257.96, 257.97, and 257.98.

2. Groundwater Monitoring System Requirements

EPA received comments that supported establishing more prescriptive requirements for 

the design of the groundwater monitoring system. For example, one commenter argued that 

three downgradient wells are insufficient to ensure detection of leakage from the very large 

disposal units typically used for CCR; due to uncertainty in flow directions, the perimeter of the 

CCR disposal unit must be monitored on its cross-gradient, as well as downgradient sides. The

commenter suggested that the minimum number of non-background monitoring wells should 

instead be three, plus one for every 500 feet of downgradient and cross-gradient perimeter of the 

CCR disposal unit (i.e., if the perimeter length adds up to 1200 feet, the minimum number of 

wells would be five), and that wells should be spaced no more than 500 feet apart along the 

downgradient and cross-gradient perimeter. EPA also received many comments arguing that the 

minimum requirements were overly prescriptive, and that the final rule should instead allow a 

professional engineer or hydrologist to design “an alternative, but equally effective, groundwater 

monitoring program.” The majority of comments on groundwater monitoring systems requested 

that EPA not promulgate requirements that would be incompatible with state requirements.

The final rule provisions are fundamentally the same as those in the proposal, although 
Document submitted to conclude E.O.12866 Review

352

EPA has also added language to the regulations to better clarify how the requirements in the 

various sections collectively operate. The final rule establishes a general performance standard 

that all groundwater monitoring systems must meet: All groundwater monitoring systems must 

consist of a sufficient number of appropriately located wells (at least one upgradient and three 

downgradient wells) in order to yield groundwater samples from the uppermost aquifer that 

represent the quality of background groundwater and the quality of groundwater passing the 

CCR waste boundary. This is the same performance standard included in the proposed rule. The 

objective of a groundwater monitoring system is to intercept groundwater to determine whether 

the groundwater has been contaminated by the CCR disposal unit. Early contaminant detection 

is important to allow sufficient time for corrective measures to be developed and implemented 

before sensitive receptors are significantly affected. To accomplish this, the rule requires that 

wells be located to sample groundwater from the uppermost aquifer at the waste unit boundary. 

These requirements have been adopted without fundamental change from the proposal.

Because hydrogeologic conditions vary so widely from one site to another, the rule does 

not prescribe the exact number, location and depth of monitoring wells needed to achieve the 

general performance standard. Rather, the rule requires the owner or operator to install a 

minimum of one upgradient and three downgradient wells, and any additional monitoring wells 

necessary to achieve the general performance standard of accurately representing the quality of 

the background groundwater and the groundwater passing the waste boundary of the CCR unit. 

The number, spacing, and depths of the monitoring wells must be determined based on a 

thorough characterization of the site, including a number of specifically identified factors 

relating to the hydrogeology of the site (e.g., aquifer thickness, groundwater flow rates and 

direction). Further, any owner or operator who determines that the specified minimum number 
Document submitted to conclude E.O.12866 Review

353

of wells is adequate must provide a factual justification for that decision. Factors that may 

substantiate a reduced density of groundwater monitoring wells includes simple geology (i.e., 

horizontal, thick, homogenous strata that are continuous across site, with no fractures, faults, 

folds, or solution channels), a flat and constant hydraulic gradient, uniform hydraulic 

conductivity, low seepage velocity, and high dispersivity potential.

In essence, the rule establishes a presumption that the minimum of one upgradient and 

three downgradient wells is not sufficient, and requires the owner or operator to rebut that 

presumption in order to install only this minimum. This is fundamentally consistent with the 

proposed rule, which required the installation of a system that would achieve the general 

performance standard, as well as the “minimum” of one upgradient and three downgradient 

wells. The final regulation merely makes more explicit that both of these requirements must be 

met. 

EPA considered establishing a more prescriptive set of requirements, including a 

specified number, location, and design of monitoring wells, but because of the highly site 

specific nature of developing an adequate groundwater monitoring system, determined that it 

lacked sufficient information to be able to design a single groundwater monitoring system that 

would be nationally protective at all sites. A properly designed system must account for too 

many variables, most of which are highly dependent on the individual characteristics of the unit 

and the facility site. Consequently, the final rule leaves the exact system design to be determined 

by those at the site, including a qualified professional engineer, who can tailor the design of the 

system to the unit and site conditions. 

Nevertheless EPA is confident that the parameters laid out in the regulation will ensure 

that the design of groundwater monitoring systems at CCR facilities will be protective. As a 
Document submitted to conclude E.O.12866 Review

354

practical matter, EPA expects that there will be few cases, if any, where four wells will be 

sufficient, given that this requirement was originally developed for hazardous waste management 

units that are typically much smaller than CCR units. As mentioned above, a small unit with 

simple geology, a flat and constant hydraulic gradient, uniform hydraulic conductivity, low 

seepage velocity, and high dispersivity potential would be the type of unit for which the 

minimum number of wells could be sufficient to meet the overall performance standard.

Although EPA is finalizing a requirement for one upgradient and three downgradient wells as a 

regulatory minimum, the Agency expects large CCR units to have many more wells because 

most CCR sites have hydrologic settings that are too complex for the regulatory minimum to be 

adequate. Facilities with large CCR units could have as many as thirty or more downgradient 

wells. This is because the placement and spacing of detection monitoring wells along the 

downgradient perimeter of the CCR disposal unit must be based on the abundance, extent, and 

physical/chemical characteristics of the potential contaminant pathways. All potential pathways 

need to be monitored. 

Therefore, even though EPA is not requiring a specific number of wells, the Agency is 

confident that the combination of the requirements will ensure that protective groundwater 

monitoring systems will be installed. The owner or operator is required to install a sufficient 

number of wells to meet the performance standard in § 257.91(a)(1) and (2), provide a 

justification if they determine the required minimum is adequate, and have a qualified 

professional engineer certify that their groundwater monitoring system has been designed and 

constructed to ensure that the groundwater monitoring will meet this performance standard—i.e., 

accurately represent the quality of groundwater that has not been affected by leakage from any 

CCR disposal unit – that is, groundwater from background wells and the quality of groundwater 
Document submitted to conclude E.O.12866 Review

355

passing the waste boundary. 

The final rule establishes certain parameters regarding the location of the wells. 

Upgradient background wells must be located beyond the upgradient extent of potential 

contamination. However, groundwater quality in areas where the geology is complex can be 

difficult to characterize. If the facility is new, groundwater samples collected from both 

upgradient and downgradient locations prior to waste disposal can be used to establish 

background water quality. Downgradient wells to monitor for any contaminants leaking into the 

groundwater must be located at the hydraulically downgradient perimeter (i.e., the edge) of the 

CCR unit or at the closest practical distance from this location. 

Determining background groundwater quality by sampling wells that are not 

hydraulically upgradient may be necessary where hydrogeologic conditions do not allow the 

owner or operator to determine which wells are hydraulically upgradient (e.g., floodplains, where 

nearby surface water can influence groundwater). In such cases, the rule allows the owner or 

operator to establish groundwater quality at existing units by locating wells that are not 

upgradient under certain conditions (§ 257.91(a)(1)). This provision may be used when 

hydrogeologic conditions do not allow the owner or operator to determine which wells are 

hydraulically upgradient and when sampling at other wells will provide data establishing 

background groundwater quality that is equally or more representative than that provided by 

upgradient wells. These conditions could include one or more of the following:

 The facility is located above an aquifer in which groundwater flow directions change 

seasonally.

 The facility is located near production wells that influence the direction of groundwater 

flow.
Document submitted to conclude E.O.12866 Review

356

 Upgradient groundwater quality is affected by a source of contamination other than the 

CCR disposal unit.

 The proposed or existing CCR disposal unit overlies a groundwater divide or local source 

of recharge.

 Geologic units present at downgradient locations are absent at upgradient locations.

 Karst terrain or fault zones modify flow.

 Nearby surface water (e.g., rivers) influences groundwater flow directions.

Additionally, there is nothing in the rule that would prevent the owner or operator from 

monitoring multiple aquifers in addition to the uppermost significant aquifer. Certain site 

conditions warrant more extensive monitoring requirements, as discussed in “Technical Manual 

Solid Waste Disposal Facility Criteria”, EPA530-R-93-017, USEPA, November, 1993, Chapter 

5, Subpart E, Ground-Water Monitoring and Corrective Action.

Each CCR disposal unit must have its own ground water monitoring system, unless the 

owner or operator chooses to install a multiunit groundwater monitoring system. The final rule 

specifies that if a multiunit system is installed, it must be based on the consideration of several 

factors, including the number, spacing, and orientation of the CCR disposal units, the 

hydrogeologic setting, the site history and the engineering design of the CCR disposal units. A 

multiunit groundwater monitoring system must be equally capable of detecting background and 

groundwater contamination at the CCR waste boundary as an individual monitoring system. 

This documentation must be certified by a qualified professional engineer. Whether a single or 

multi-unit system has been installed, the monitoring wells must be cased in a manner 

maintaining the integrity of the bore hole and must be maintained so as to meet design 

specifications. Both of these provisions have been adopted from the proposal without revision. 
Document submitted to conclude E.O.12866 Review

357

3. Sampling and Analysis Requirements

EPA received comment on several aspects of its proposed requirements for conducting

groundwater sampling and analyses. Specifically mentioned here, commenters raised concern 

about the number of samples required to establish background concentrations and about the 

statistical test methodologies specified in the proposal. As discussed below, EPA has modified 

the rule to account for the issues raised by these commenters. The sampling and analysis 

requirements in the final rule have otherwise been adopted from the proposed rule with only 

minor clarifications. 

The rule provides procedures for sampling monitoring wells and methods for the 

statistical analysis of groundwater monitoring of Appendix III (detection monitoring) and 

Appendix IV (assessment monitoring) constituents that may be released from CCR disposal 

units. The sampling and analysis program must include procedures and documentation for 

sample collection (including the frequency, water level measurements, well purging, field 

analyses, and sample withdrawal and collection); sample preservation and handling (including 

sample containers, sample preservation, sample storage and shipment); chain of custody control; 

analytical procedures (appropriate methods can be found in “Test Methods for Evaluating Solid 

Waste , Physical/Chemical Methods,” SW-846 (USEPA, 1986), 

http://www.epa.gov/waste/hazard/testmethods/sw846/online/index.htm ); and quality 

assurance/quality control. More information and guidance can be found in “Technical Manual 

Solid Waste Disposal Facility Criteria,” EPA530-R-93-017, USEPA, November, 1993, Chapter 

5, Subpart E, Ground-Water Monitoring and Corrective Action, as well as the “Unified 

Guidance Document: Statistical Analysis of Groundwater Monitoring Data at RCRA Facilities,” 

March 2009, EPA 530/R-09-007.
Document submitted to conclude E.O.12866 Review

358

Similar to the approach used in designing a groundwater system, the final rule adopts a 

combination of a general performance standard for groundwater sampling and analytical 

methods, along with particular technical specifications that must be met. The general 

performance standard requires that the method used must accurately measure hazardous 

constituents and other monitoring parameters. In addition, the rule specifies that groundwater 

elevations must be measured in each monitoring well immediately prior to sampling. Also, the 

rate and direction of the groundwater flow in the uppermost aquifer must be determined each 

time groundwater is sampled. Further, the rule specifies that the background groundwater 

quality must be established at a hydraulically upgradient well for each of the monitoring 

parameters or constituents required by the applicable groundwater monitoring program, except as 

provided in § 257.91. The number of samples collected to establish groundwater quality data 

must be consistent with the appropriate statistical procedures determined for the specific 

statistical method chosen. The sampling must also be conducted to account for both seasonal 

and spatial variability in groundwater quality.

To establish background levels, the proposed rule required that “a minimum of four 

independent samples from each background and downgradient well must be collected and 

analyzed...” 75 FR 35247-35248 (proposed §§ 257.93(f) and 257.94(b)). This is the same 

sampling protocol that EPA adopted for both the subtitle C and part 258 groundwater monitoring 

requirements.

EPA received comments criticizing this sampling protocol. Several commenters stated 

that more than the required four samples were needed in order to adequately represent 

background water quality and reduce the number of false negatives. For example, one 

commenter argued that EPA should require a minimum of one year of monthly monitoring of 
Document submitted to conclude E.O.12866 Review

359

background concentrations to characterize fluctuations in parameters that will be evaluated 

statistically. The commenter claimed that this would also help to ensure that quarterly 

monitoring events are properly timed. Another comment stated that more data points and time 

were needed to ensure statistical confidence in the data. By contrast, another commenter objected 

to the requirement to obtain four independent samples, arguing that this requirement was 

unnecessary and should be deleted. The commenter argued that this requirement was 

inconsistent with EPA’s Unified Guidance (EPA, 2009) for Statistical Analysis of Groundwater 

Monitoring Data at RCRA Facilities, which specifies that replicate samples (i.e., multiple 

samples from the same location during a given sampling event) should typically be limited to the 

collection of two samples from the same location, rather than four. Another commenter 

requested clarification on the number of samples required when establishing background levels 

that would serve as the point of comparison in determining whether a statistically significant 

increase over background levels had occurred. 

In response to these comments, EPA reviewed the available information to determine 

whether revisions to the proposed requirements were warranted. 

More recent information developed since the promulgation of the subtitle C and part 258 

groundwater monitoring requirements indicates that statisticians now generally consider sample 

sizes of four or less to be insufficient for good statistical analysis because the observations are 

too few to adequately characterize the parameters of the population. Tests utilizing a small 

background sample size have low statistical performance in terms of power and per-test false 

positive rates. In 2009, EPA issued a guidance document that accounts for more recent scientific 

developments, “Unified Guidance Document: Statistical Analysis of Groundwater Monitoring 

Data at RCRA Facilities,” March 2009, EPA 530/R-09-007. This guidance recommends a 
Document submitted to conclude E.O.12866 Review

360

minimum of eight to ten independent background observations be collected before performing 

the first statistical test. Sample sets of 20 are considered optimal.

RCRA regulations are predicated on having appropriate and representative background 

measurements. Samples should be tested against data which best represent current 

uncontaminated conditions. In addition, as discussed further in Unit VI.K.5 below, the detection 

of a statistically significant increase over background concentrations of the constituents of 

concern will have serious implications for unlined surface impoundments, as these units will be 

required to close whenever the facility makes such a finding. EPA is also cognizant of the 

significant differences between the subtitle C and part 258 regulations and the final regulations 

being promulgated for CCR units. Both the subtitle C and the part 258 MSWLF requirements 

are implemented under permit programs, under which regulatory authorities are specifically 

authorized to establish more stringent requirements to account for scientific advances (among 

other things). EPA expects that current permits generally specify a greater number of samples

than the minimum laid out in the regulations (i.e., more than four) to determine background

concentrations. And because of this it is less critical that those regulations (subtitle C and part 

258) reflect the most current science. By contrast, as previously discussed, the provisions

adopted under this rule are self-implementing, and will only be updated through a subsequent 

rulemaking. Accordingly, the Agency agrees with the comments that four samples would be 

insufficient and has amended the rule to require the owner or operator to collect, at a minimum,

eight statistically independent and identically distributed (spatially invariant) samples from each 

well for each monitoring parameter. Although still a small sample size by statistical standards, 

eight independent observations allows for minimally acceptable estimates of variability and 

evaluation of trend and goodness-of fit. While more samples, including a full year of background 
Document submitted to conclude E.O.12866 Review

361

monitoring, would be scientifically ideal, the Agency selected eight samples by balancing the 

minimum number needed to ensure the scientific accuracy of the results against the need to 

expedite initiating the groundwater monitoring process of detecting exceedances, along with any 

necessary corrective action at these facilities.

Background sampling (i.e., the requirement to collect eight statistically independent 

samples from each well) must be completed for all Appendix III and IV constituents by the end 

of the 24 month period to begin implementation of the groundwater monitoring program.

EPA has also revised the regulatory text relating to the number of samples that must be 

collected during subsequent sampling events after background concentrations have been 

established to clarify how the various provisions collectively operate. Consistent with the 

proposal, the final rule requires the owner or operator to collect and analyze the number of 

samples from each well necessary to be consistent with the statistical test selected under § 

257.93(e) and with the unique characteristics of the site, but at minimum, to collect at least one 

sample from each background and downgradient well. In cases where the groundwater is “wellbehaved” one sample from each compliance well could be all that the owner or operator would 

need to conduct the necessary comparisons. But if statistical assumptions are not met (e.g., the 

observations are not statistically independent or background well data show trends) a comparison 

based on a single observation will not yield a significant result, and will likely result in a false 

positive. Further, detection monitoring tests, such as Student’s t-test, look at the difference 

between the sample means (e.g., upgradient vs downgradient) to determine when an observed 

difference should be considered more than a chance fluctuation. Every t-test assumes that the 

observations that make up each data group meet the requirements of statistical independence and 

stationarity. Therefore, the larger the sample size the more significant the result. In other words, 
Document submitted to conclude E.O.12866 Review

362

a facility can choose to use only one observation (a group size of one), but the chances are good 

that the result derived would be non-significant, since there are many reasons sample means can 

vary. Consequently, it is likely to be in the facility’s best interest to take more samples than the 

minimum, particularly in the early stages of monitoring. As monitoring continues, each 

successive sample will be added to the sampling data base, which will increase the confidence in 

the statistical analyses performed. Additional guidance on sample size can be found in the 

“Unified Guidance Document: Statistical Analysis of Groundwater Monitoring Data at RCRA 

Facilities,” March 2009, EPA 530/R-09-007. 

The requirements for applying statistical procedures in the rule are the same as those

included in the proposed rule, which were based on the statistical procedures used in the 

MSWLF regulations. The rule requires the owner or operator to select from among the listed 

statistical procedures based on a determination that the test is appropriate for evaluating 

groundwater at that site. The statistical method chosen must be appropriate for the distribution of 

chemical parameters or hazardous constituents. The rule has been revised to include the 

clarification that normal distributions of data values shall use parametric methods and nonnormal distributions shall use non-parametric methods. The rule identifies four statistical 

procedures, along with an alternative procedure that must meet the performance standard of §

257.93(g). The four specific statistical procedures provided in this final rule are: (1) a parametric 

analysis of variance followed by multiple comparison procedures to identify statistically 

significant evidence of contamination; (2) an analysis of variance based on ranks followed by 

multiple comparison procedures to identify statistically significant evidence of contamination; 

(3) a tolerance or prediction interval procedure; and (4) a control chart approach. The 

performance standard for the alternative method in subsection (g) is the same as the performance 
Document submitted to conclude E.O.12866 Review

363

standard in the proposal, with minor revisions. EPA has deleted the performance standard 

“protect human health and the environment” in subsections (3), (4) and (5). While that standard 

is perfectly appropriate in a context in which a regulatory authority will apply the standard, EPA 

is concerned that a professional engineer will be unable to certify that any alternative statistical 

method meets that standard. EPA received comments from professional engineers raising 

concern about their ability to certify that many of the requirements in the proposed rule had been 

met without further specification or clarification. To address those concerns, in those three 

provisions EPA has substituted a more objective performance standard that more precisely 

defines the relevant issues to be considered. Specifically, the subsections now specify that those 

approaches must be “at least as effective as any other approach in this section for evaluating 

groundwater.” 

The data objectives of the monitoring, in terms of the number of samples collected and 

the frequency of collection, must be consistent with the statistical method selected. Guidance on 

selecting a specific method is described in “Unified Guidance Document: Statistical Analysis of 

Groundwater Monitoring Data at RCRA Facilities,” March 2009, EPA 530/R-09-007. The 

owner or operator must indicate in the operating record the statistical method that will be used in 

the analysis of groundwater monitoring results. 

The owner or operator must conduct the statistical comparisons between upgradient and 

downgradient wells within 90 days of completion of each sampling event and receipt of validated 

data. The statistical comparison must be conducted in order to determine if a statistically 

significant increase has occurred over background levels for each parameter or constituent 

required in the particular groundwater monitoring program that applies to the unit as determined 

under §§ 257.94(a) or 257.95(a). This has been adopted without revision from the proposal.
Document submitted to conclude E.O.12866 Review

364

EPA is finalizing as proposed the prohibition in § 257.93(b) on field filtering 

groundwater samples because filtration of samples for metals analyses will not provide accurate 

information concerning the mobility of metals contaminants, the primary objective of 

groundwater sampling. Metal contaminants may move through fractured and porous media not 

only as dissolved species, but also as precipitated phases, polymeric species, or adsorbed to 

particles of colloidal dimensions (< 10 microns). For an assessment of mobility, all mobile 

species must be considered, including suspended or colloidal particles acting as absorbents for 

contaminants. Filtration of groundwater samples for metals analyses will not provide accurate 

information concerning the mobility of metal contaminants because some mobile species in 

solution are likely to be removed by filtration before chemical analysis. Significant 

underestimations of mobility may result if filters (typically 0.45 micron) are used to separate 

dissolved and particulate phases. 

In its approach to sampling EPA is specifying in the final rule that owners and operators 

use ‘total recoverable metals’ concentrations in measuring groundwater quality. Measurement of 

total recoverable metals captures both the particulate fraction and dissolved fraction of metals in 

natural waters. Exceedances of ambient water criteria on a total recoverable basis are an 

indication that metal loadings could be a stress to an ecosystem. 

One commenter argued that to prohibit field filtering would potentially bias the results 

artificially high, particularly at sites where low yielding formations or naturally high levels of 

turbidity in groundwater are encountered. However, high turbidity can also be the consequence 

of faulty well design and/or construction, which causes the introduction of foreign materials 

(high turbidity) through created fracture pathways. A properly designed well should allow for 

sufficient groundwater flow for sampling, minimize the passage of materials into the well, and 
Document submitted to conclude E.O.12866 Review

365

exhibit sufficient structural integrity to prevent collapse of the intake structure. It is vital that the 

well provide a representative hydraulic connection to the geologic formation of interest. 

Otherwise the water chemistry information cannot be correctly interpreted in relation to 

groundwater flow or transport of chemical constituents.

Sampling with no filtration means that increased importance is placed on proper well 

construction and purging sampling procedures to eliminate or minimize sources of sampling 

artifacts. There should be nothing in the well design that will lead to high levels of turbidity. 

Groundwater sampling should be conducted utilizing EPA protocol low stress (low-flow) 

purging and sampling methodology, including measurement and stabilization of key indicator 

parameters prior to sampling. For purposes of sampling, this final rule presumes that a properly 

constructed well is capable of yielding groundwater samples with low turbidity (≤5 NTU), and 

by knowing the cause of turbidity the qualified professional engineer will be able to optimize 

well performance and reduce turbidity levels, eliminating the need for filtration.

EPA is revising § 257.93(i)(2) to specify a time period of 90 days to determine if a 

statistically significant increase over background concentrations of one of more of the 

contaminants has been detected. As proposed, this section specified: “Within a reasonable 

period of time after completing sampling and analysis, the owner or operator of the CCR landfill 

or surface impoundment must determine whether there has been a statistically significant 

increase over background at each monitoring well.” Commenters pointed out that this section of 

the regulation was very vague, and potentially unenforceable. Several commenters suggested

that once sampling and analysis had been completed, 90 days would be a reasonable amount of 

time to complete the statistical analysis to determine whether an exceedance had occurred. No 

commenter suggested a longer period of time was necessary and that timeframe is consistent 
Document submitted to conclude E.O.12866 Review

366

with the Agency’s experience of the timeframes necessary to complete such analyses. 

Accordingly, we have revised the provision to require the determination of a statistically 

significant increase to be made within 90 days of sampling and analysis.

4. Detection Monitoring Program 

With three exceptions, EPA is finalizing the regulatory provisions relating to detection 

monitoring as proposed. The three revisions are the Appendix III list of monitoring parameters; 

the required number of samples to determine background concentrations; and the availability of 

an option to conduct detection monitoring on a less frequent basis due to a lack of groundwater.

The detection monitoring phase of the ground water monitoring program in this rule 

requires that the owners or operators of CCR units establish background concentrations for all 

monitoring parameters (Appendix III and IV of Part 257) and sample at least semiannually 

during the active life of the facility, closure, and post closure periods for a set of detection 

monitoring indicator parameters (Appendix III of Part 257). 

In response to comments, EPA has revised Appendix III to delete conductivity and 

sulfide from the list of monitoring parameters and to add calcium. Thus, the list of parameters 

included on the detection monitoring list is boron, calcium, chloride, fluoride, pH, sulfate and 

total dissolved solids (TDS). The Agency has deleted conductivity from the detection 

monitoring program because it is merely a proxy for TDS, which is already included on the list 

of parameters to analyze during detection monitoring. The Agency has also deleted sulfide 

because it occurs in groundwater only under strongly reducing conditions, and such conditions 

are rather rare at CCR disposal facilities. Calcium is being added to Appendix III because it is an 

indicator of the extent of leaching from fly ash and FGD gypsum and because of the strong 

demonstrated link between the leaching of calcium and arsenic, which is one of the primary risk 
Document submitted to conclude E.O.12866 Review

367

drivers identified in the risk assessment. 

As discussed in the preceding section, in detection monitoring, a minimum of eight

independent samples from each background and downgradient well must be collected and 

analyzed for the Appendix III and IV parameters no later than 24 months from the effective date 

of the rule. During subsequent sampling events, at least one sample from each background and 

downgradient well must be collected and analyzed, although the total number of samples must be 

consistent with the statistical procedures selected and with the performance standard in § 

257.93(g). See discussion above in section 3. Sampling and Analysis Requirements.

Under the proposed rule, monitoring would be required no less frequently than 

semiannually. In the final rule, semiannual sampling remains the general requirement; however, 

in response to comments, EPA has decided to include a provision that would allow an alternative 

sampling frequency if there is not adequate groundwater to flow to sample wells semiannually. 

Specifically, EPA received comment stating that there may be instances where there simply is 

not enough water available to collect and analyze on a semiannual basis, especially in western 

climates where the rate of groundwater recharge may be too slow or a lack of precipitation 

exists. The commenter also provided an example demonstrating that mining practices in 

adjacent areas can greatly alter the groundwater flow. Accordingly, EPA has included a 

provision to address the situations where there is insufficient ground water available to collect 

and analyze samples around CCR disposal units on a semiannual basis. 

An owner or operator seeking to establish an alternative frequency must demonstrate that 

less frequent monitoring is necessary based on the following three factors: (1) lithology of the 

aquifer and the unsaturated zone; (2) hydraulic conductivity of the aquifer and the unsaturated 

zone; and (3) groundwater flow rates. In addition, the rule requires the owner or operator to 
Document submitted to conclude E.O.12866 Review

368

demonstrate that any alternate sampling frequency would be no less effective in ensuring that 

any leakage from the CCR disposal unit will be discovered within a timeframe that does not 

materially delay the initiation of any necessary remediation measures. The owner or operator 

must have a qualified professional engineer certify that the alternative (i.e., less frequent) 

monitoring will achieve this performance standard. The final rule also specifies that any

alternate frequency during the active life (including closure) and the post-closure care period 

shall be no less than annual. As noted, the owner or operator will bear the burden of justifying an 

alternate frequency under this regulation, and in any court proceeding brought to enforce these 

requirements. This means that any uncertainty or lack of information will be weighed against the 

entity seeking to justify the alternate frequency.

Consistent with the proposed rule, if the owner or operator determines that there is a 

statistically significant increase (SSI) over background for one or more of the parameters listed 

in Appendix III at any monitoring well at the waste boundary, the owner or operator must place a 

notice in the operating record and on the facility’s internet site indicating which parameters have 

shown statistically significant changes from background levels and notify the State Director. 

The facility must also then establish an assessment monitoring program and begin 

monitoring within 90 days. The owner or operator has the opportunity to demonstrate that a 

source other than the CCR unit caused the statistically significant increase or that the statistically 

significant increase resulted from error in sampling, analysis, statistical evaluation or a natural 

variation in groundwater quality. Within 90 days, the owner or operator must prepare a report 

documenting this demonstration which must then be certified by a qualified professional 

engineer verifying the accuracy of the information in the report. If a successful demonstration is 

made within 90 days, the owner or operator may continue detection monitoring. If a successful 
Document submitted to conclude E.O.12866 Review

369

demonstration is not made within 90 days, the owner or operator must initiate assessment 

monitoring. 

Commenters raised concern that 90 days would not be sufficient to complete all of the 

activities necessary to determine whether the detection of an SSI was from another source than 

the CCR unit or was based on inaccurate result. The Agency recognizes that in some 

circumstances it could take more than 90 days to resample and have laboratories conduct new 

analyses, or to conduct field investigations to determine that another source is causing the 

contamination. As a result, § 257.94(e)(3) does not place an ultimate time limit for owners and 

operators to complete the demonstration. However, if after 90 days the owner or operator has 

not made a successful demonstration, (s) he must begin an assessment monitoring program. At 

this stage, there is evidence to indicate that a release has occurred from the CCR unit, and while 

EPA agrees that the facility may want to confirm that the information is accurate, it is critical 

that the facility not delay indefinitely the more targeted monitoring to determine whether a 

constituent of concern is contaminating groundwater. It would not be consistent with the 

statutory standard to allow a facility unlimited time to delay taking reasonable steps to assess, 

and if necessary, address potential contamination by continuing to resample until they obtain a 

“better” answer. Moreover, initiation of an assessment monitoring program does not involve an 

irretrievable commitment of resources or even a significant investment by the facility, but only 

requires the facility to begin more targeted sampling for constituents of concern. This represents 

a reasonable first step to address a potential threat to ground water. This requirement is also in 

the MSWLF Part 258 regulations. For more information see 56 FR 51078 (October 9, 1991).

Subsequent to initiating the assessment monitoring program, if an owner or operator 

demonstrates that the statistically significant increase resulted from an error in sampling, 
Document submitted to conclude E.O.12866 Review

370

analysis, statistical evaluation, or natural variation in groundwater quality, or was caused by a 

source other than the CCR disposal unit, the owner or operator may cease assessment monitoring 

and return to detection monitoring. If the demonstration is successful, the owner or operator

must have the demonstration certified by a qualified professional engineer, and is required by §

257.94(e)(3) to place a notice in the operating record, and on the internet site and send a copy of 

the report to the State Director. 

5. Assessment Monitoring Program

EPA is adopting an assessment monitoring program that is largely identical to the 

program laid out in the proposal. However, as discussed in more detail below, some revisions 

have been made; some were made in response to comments, but most are conforming changes 

made to be consistent with changes adopted in other provisions, such as the detection monitoring 

program described previously,

Consistent with the proposed rule, if any of the detection monitoring parameters are 

detected at a statistically significant level over the established background concentrations, the 

owner or operator must proceed to the next step, assessment monitoring. Assessment 

monitoring requires annual sampling and analysis for the full list of hazardous constituents 

included in Appendix IV. The number and frequency of samples required for assessment 

monitoring are the same as those established for detection monitoring. See discussion above in 3.

Sampling and Analysis Requirements.

EPA has also revised the list of constituents in Appendix IV by deleting the following 

constituents and parameters: aluminum, boron, chloride, copper, iron, manganese, pH, sulfate, 

sulfide, and TDS; and adding the following constituents: cobalt, lithium, and radium 226 and 

228 combined. The following constituents and parameters are being removed from Appendix IV 
Document submitted to conclude E.O.12866 Review

371

because they are on Appendix III and therefore will continue to be monitored throughout 

assessment monitoring: boron, chloride, pH, sulfate and TDS. Although fluoride is on 

Appendix III, we are also retaining it on Appendix IV because it does have an MCL and was 

found to pose risks in the 2014 risk assessment, and therefore is appropriately considered to be a 

constituent that is relevant for purposes of corrective action. Aluminum, copper, iron, 

manganese, and sulfide have been removed because they lack maximum contaminant levels

(MCLs) and were not shown to be constituents of concern based on either the risk assessment

conducted for this rule or the damage cases (see Unit X). Cobalt has been added to Appendix IV 

because cobalt was found to be a risk driver in the 2014 risk assessment, based on certain waste 

management disposal practices that lead to highly acidic wastes conditions. Lithium is being 

added to Appendix IV because it has been detected in several proven and potential damage cases 

at levels exceeding EPA’s Regional Screening Level (RSL) of soil to groundwater and has been 

determined as potentially toxic if consumed concurrently with certain drug types.[1] Radium 226 

and 228 combined (the sum of the radioactive isotopes radium-226 and radium-228) is being 

added because there is evidence from several damage cases of exceedances of gross alpha, 

indicating that radium from the disposal of CCR may be problematic. Appendix IV now contains 

antimony, arsenic, barium, beryllium, cadmium, chromium, cobalt, fluoride, lead, lithium, 

mercury, molybdenum, selenium, thallium and radium 226 and 228 combined.

If any Appendix IV constituents are detected in any Appendix IV analyses, the owner or 

 

[1] EPA’s Regional Screening Level (RSL) Soil to Groundwater Supporting Table (TR=1E-6, HQ=1) May 

2014/Mid-atlantic Risk assessment:

http://www.epa.gov/reg3hwmd/risk/human/rb-concentration_table/Generic_Tables/index.htm; and Health 

Consultation: Chesapeake ATGAS 2H Well Site Leroy Hill Road, Leroy, Leroy Township, Bradford 

County, Pennsylvania, October 29, 2013. U.S. Department of Health and Human Services, Agency for 

Toxic Substances and Disease Registry Division of Community Health Investigations Atlanta, Georgia. 

http://www.atsdr.cdc.gov/.
Document submitted to conclude E.O.12866 Review

372

operator must notify the State Director and continue to monitor, at least semiannually, for both 

the specific constituents in Appendix IV that were detected and all parameters in Appendix III. 

EPA has decided to also include a provision to allow an alternative sampling frequency if there is 

not adequate groundwater to flow to sample wells semiannually, consistent with the revised 

provision adopted for the detection monitoring program. If the owner or operator demonstrates 

at any time during assessment monitoring that all of the detected Appendix III and IV 

constituents are at or below background values for two consecutive sampling events, (s)he must 

notify the State and may return to detection monitoring. In general, EPA expects that Appendix 

III constituents are unlikely to remain elevated once measures have been taken to address the 

release of the detected Appendix IV constituents. But should Appendix III constituent levels 

remain elevated, detection monitoring continues to be necessary to determine whether another 

source of contamination is present.

After obtaining the sampling results the owner or operator must place a notice in the 

operating record and on the facility’s internet site indicating which Appendix IV constituents 

have been detected and notify the State Director. Within 90 days and on at least a semiannual 

basis thereafter, the owner or operator must resample all wells, conduct analyses for all 

parameters in Appendix III and for those constituents in Appendix IV that were detected in the 

initial assessment monitoring sampling event. The results of this resampling must be placed in 

the owner or operator’s operating record, as well as its publicly accessible internet site. The 

results of the resampling must also be sent to the State Director. These provisions have been 

adopted without change from the proposal. 

For each Appendix IV constituent that is detected, a ground water protection standard 

must be set. The groundwater protection standards must be the MCL or the background 
Document submitted to conclude E.O.12866 Review

373

concentration level for the detected constituent, whichever is higher. If there is no MCL 

promulgated for a detected constituent, then the groundwater protection standard must be set at 

background. The proposed rule would have allowed the owner or operator to establish an 

alternative groundwater protection standard for constituents for which MCLs have not been 

established provided that the alternative groundwater protection standard has been certified by an 

independent registered professional engineer and the state has been notified that the alternative 

groundwater protection standard has been placed in the operating record and on the owner’s or 

operator’s publicly accessible internet site. This provision had been adopted from the part 258 

regulations, but was determined to be inappropriate in a self-implementing rule, as it was 

unlikely that a facility would have the scientific expertise necessary to conduct a risk assessment, 

and was too susceptible to potential abuse. Additionally, numerous comments were received 

suggesting that only those constituents with MCLs be included in Appendix IV. The 

commenters were concerned that only MCLs are enforceable. With the exception of cobalt, 

lithium and molybdenum (included on Appendix IV because of their relevance in the risk 

assessment and damage cases), all Appendix IV constituents have an MCL. In the proposed rule, 

as stated above, owner or operators were allowed to establish certain types of alternative 

groundwater protection standards. In the final rule, if a constituent has no MCL (i.e., cobalt, 

lithium and molybdenum), their groundwater protection standards will be their background 

levels. These background standards are sufficiently precise that they are enforceable. 

The owner or operator must compare the levels of any detected Appendix IV constituents 

to the appropriate groundwater protection standard. If the concentrations of all Appendix IV 

constituents are shown to be at or below background values for two consecutive sampling events 

using the statistical procedures required by § 257.93, the owner or operator of the CCR disposal 
Document submitted to conclude E.O.12866 Review

374

facility must place that information in the operating record and on the facility’s internet site and 

notify the State Director. The owner or operator may then return to detection monitoring.

If the concentrations of any Appendix III or IV constituents are above background values, 

but all concentrations are determined to be below the groundwater protection standard using the 

statistical procedures required by this rule, the owner or operator of the CCR disposal facility 

must continue assessment monitoring program. 

If, however, the monitoring indicates a statistically significant increase for any Appendix 

IV constituent over the groundwater protection standard, the owner or operator is required to 

notify the State Director and local officials of this finding and place a notice in the operating 

record and on the owner or operator’s publicly accessible internet site. 

The owner or operator also must characterize the nature and extent of the release. As part 

of characterizing the nature and extent of the release, the owner or operator must install 

additional wells, as necessary to define the contaminant plume(s) and collect data on the nature 

and estimated quantity of the material released. Adequate characterization of the release is 

critical in designing and effectively implementing a protective corrective action program if 

groundwater remediation is necessary. The purpose of these additional wells is to delineate the 

contaminant plume boundary and to eventually demonstrate the effectiveness of corrective action 

in meeting the groundwater protection standard. 

Because the requirements for additional monitoring are entirely specific to the site 

conditions and the size and nature of the release, the Agency is not able to set requirements that 

precisely specify the location or the number of additional wells that must be installed. Instead 

EPA has adopted an approach that corresponds to the approach to designing the original 

groundwater monitoring system under § 257.91. The regulations establish a general performance 
Document submitted to conclude E.O.12866 Review

375

standard (“install additional wells as necessary to define the contaminant plume”) and specify a 

true minimum of installing at least one well at the facility boundary in the direction of 

contaminant migration in order to ascertain whether the contaminants have migrated past the 

facility boundary. The regulations also establish a rebuttable presumption that this minimum is 

insufficient, requiring the owner or operator to justify a decision to install only this minimum.

The requirement to justify the decision to only install the minimum number of additional wells is 

a revision from the proposal that has been adopted to be consistent with the Agency’s overall 

approach to developing an effective groundwater monitoring system.

The Agency has also added some clarification to the proposed requirement to 

characterize the nature and extent of the release, by requiring the owner or operator to collect 

data on the nature and estimated quantity of material released, including specific information on 

the constituents listed in Appendix IV and the levels at which they are present in the material 

released. This information will be necessary to help the owner or operator characterize the 

release and assist in ultimately deciding on a remedy.

If contamination has migrated off-site, the owner or operator must notify individuals who 

own land or reside on land overlying the plume.

In addition to characterizing the nature and extent of the release, the owner or operator 

must initiate an assessment of corrective measures within 90 days of finding a statistically 

significant increase over background concentrations, and select the appropriate remedy. During 

this phase, the owner or operator is required to continue at least semiannual monitoring (or an 

alternative frequency, no less than annual) for all Appendix III constituents and for those 

Appendix IV constituents exceeding the groundwater protection standard. To be consistent with 

the provisions in detection monitoring, EPA has included a provision that would allow the owner 
Document submitted to conclude E.O.12866 Review

376

or operator to demonstrate that a source other than their CCR unit caused the contamination or 

that the statistically significant increase above ground water protection standards resulted from 

error in sampling, analysis, statistical evaluation, or natural variation in groundwater quality. 

This alternative option will not delay compliance with the next phase of the groundwater 

monitoring and corrective action program. Thus, until such a demonstration is made, the owner 

or operator must comply with the other requirements of this section, including initiating the 

assessment of corrective measures. At this stage, the evidence that the CCR unit is leaking is 

stronger, and the owner or operator has previously had the opportunity to demonstrate that the 

finding was made in error under the detection monitoring program, so no further delay in 

initiating measures to address any groundwater contamination is warranted. 

Another change since the proposal is that in addition to complying with all of the 

corrective action requirements—i.e., initiating an assessment of corrective measures, followed by 

selection of a remedy and implementation of a corrective action program--if the unit is an 

unlined surface impoundment, it must either retrofit or initiate closure. Further, where the 

facility has chosen to install a multi-unit ground water monitoring system, the detection of an SSI 

of an Appendix IV constituent would trigger the corrective action and closure (or retrofit) of all

of the unlined surface impoundments covered by that monitoring system, as there will be no way 

to isolate a particular unlined unit as the source of the contamination. These requirements are 

discussed in more detail in the Closure section.

6. Assessment of Corrective Measures.

This section of the regulations also largely mirrors the analogous provisions in the 

proposed rule. EPA added some language to reflect that this section is not limited to the 

remediation of groundwater from a leaking CCR unit but will also apply to contamination caused 
Document submitted to conclude E.O.12866 Review

377

by any kind of release from a CCR unit. EPA also made some minor revisions in response to 

comments, and some editorial changes to conform this provision to changes made in other 

sections of the rule. 

Consistent with the proposal, § 257.96(a) specifies that the assessment of corrective 

measures must be initiated within 90 days of detecting a statistically significant increase of any 

of the constituents listed in Appendix IV, at a level exceeding the groundwater protection 

standard(s), or of otherwise documenting a release of contaminants from the CCR unit. The 

regulation also requires the assessment of corrective measures to be completed in 90 days of 

such a finding, but in response to comments, EPA is adopting a provision that will allow for a 

single 60-day extension. Multiple commenters argued that 90 days was not adequate to complete 

the assessment of corrective measures. Commenters stated that for situations with complex 

hydrogeology, additional studies and sampling may be required in order to assess potential 

contributing offsite sources, background levels, and possible remedies. They stated that 

identification of remedy alternatives, collection and analysis of data used to evaluate remedy 

alternatives, and discussions with vendors/contractors regarding availability of labor and 

materials are all critical steps in the remedy selection process. As explained in the “Technical 

Manual Solid Waste Disposal Facility Criteria,” EPA530-R-93-017, USEPA, November, 1993, 

Chapter 5, Subpart E, Ground-Water Monitoring and Corrective Action, the owner or operator 

will need to: (1) identify and remediate the source of contamination; and (2) identify and 

remediate the known contamination. The factors that must be considered in assessing corrective 

measures include source evaluation, plume delineation, groundwater assessment and source 

control. Based on the comments received, as well as the Agency’s own experience, EPA

recognizes that there may be complex situations that require more time to develop a careful and 
Document submitted to conclude E.O.12866 Review

378

well-thought out corrective measures assessment. Therefore, the final rule has been modified to 

allow up to an additional 60 days to complete the assessment of corrective measures, provided 

that a qualified professional engineer certifies that the additional time is necessary. The initial 90 

days plus the additional 60 days, which is within the range of time suggested by the commenters, 

would provide the owner or operator up to 150 days to complete the corrective measures 

assessment, which EPA expects will be sufficient. The certification must be placed in the 

operating record, on the owner’s or operator’s website and submitted to the proper state official.

The rule requires the owner or operator to assess the effectiveness of potential remedies 

in meeting the objectives of § 257.97 by addressing at least: (1) performance, reliability, ease of 

implementation and potential impacts; (2) time requirements; and (3) institutional requirements. 

The proposed rule also included consideration of the costs of remedy implementation. However, 

that language came directly from the MSWLF rule in part 258. Because Congress did not 

authorize the consideration of costs in establishing minimum national standards under RCRA 

section 4004(a), we have removed this factor. In evaluating the performance, reliability, ease of 

implementation, and potential impacts of each remedy, the owner or operator should evaluate 

whether specific remedial technologies are appropriate to the problem and the ability of those 

technologies to achieve the groundwater protection standards. Analysis of a remedy’s reliability 

should include an assessment of the effectiveness of the remedy in controlling the source of the 

release and its long-term reliability. Source control measures need to be evaluated to limit the 

migration of the plume, and to ensure an effective remedy. The regulation does not limit the 

definition of source control to exclude any specific type of measure to achieve this. Remedies 

must control the source of the contamination to reduce or eliminate further releases by 

identifying and locating the cause of the release. Source control measures may include the 
Document submitted to conclude E.O.12866 Review

379

following: modifying the operational procedures (e.g., banning waste disposal); undertaking 

more extensive and effective maintenance activities (e.g., excavate waste to repair a liner 

failure); or, in extreme cases, excavation of deposited wastes for treatment and/or offsite 

disposal. Construction and operation requirements also should be evaluated. The analysis of the 

timing of potential remedies should include an evaluation of construction, start-up, and 

completion time. Timing is particularly important if contamination has migrated off-site. 

Institutional requirements such as local permit or public health requirements may affect 

implementation of the remedies evaluated and should be assessed by the owner or operator. 

The proposed rule included a provision that would allow an owner or operator to 

determine that compliance cannot be reasonably achieved with any currently available methods. 

This has been deleted from the final rule. The Agency determined that without state oversight or 

a permitting program, that provision was potentially subject to abuse and thus, inappropriate to 

include in a self-implementing rule. 

As part of evaluating potential remedies, the owner or operator must hold a public 

meeting to discuss the remedies under consideration (prior to selecting a final remedy). Once the 

owner or operator has selected a remedy, he must place a description of the selected remedy in 

the operating record, on the owner or operator’s internet site and notify the State Director.

7. Selection of Remedy

This section of the final rule has been adopted with only minor changes from the 

proposal. As in the prior section, EPA has revised certain provision to reflect that this section 

will also apply to the cleanup of contamination caused by a release from a CCR unit. EPA also 

deleted a provision that had been adopted from the part 258 regulations, but that was determined 

to be inappropriate in a self-implementing rule as it was too susceptible to potential abuse. 
Document submitted to conclude E.O.12866 Review

380

Based on the results of the corrective measures assessment conducted, the owner or 

operator must select a remedy. The selected remedy must attain all of the performance standards 

listed in subsection (b). Specifically, the remedy must protect human health and the 

environment, attain the groundwater protection standards, control the sources of releases so as to 

reduce or eliminate, to the maximum extent practicable, further releases of Appendix IV 

constituents into the environment, and comply with any relevant standards for management of 

wastes generated as a result of the remedial activities. EPA included an additional criterion more 

directly related to remediation of contamination associated with a release, such as from a 

collapse or structural failure of a CCR unit, which requires the remedy to “remove from the 

environment as much of the contaminated material that was released from the CCR unit as is 

feasible, taking into account factors such as avoiding the inappropriate disturbance of sensitive 

ecosystems.” Together, these criteria reflect the major technical components of any kind of 

clean up remedy.

The rule also specifies decision criteria to be considered by the owner or operator in 

selecting the most appropriate remedy. These include: (1) long and short term effectiveness, and 

degree of certainty of success; (2) effectiveness of remedy in controlling the source to reduce 

further releases; (3) ease or difficulty of implementation; and (4) community concerns. 

Additionally, the rule requires the owner or operator to specify a schedule for implementing and 

completing the remedial activities. The rule requires the owner or operator to set the schedule 

because it is impossible for EPA to establish a single schedule appropriate for all possible 

situations; the schedule will necessarily depend on the nature and size of the contamination, 

among other factors. The rule outlines six factors to be considered in establishing a schedule for 

completing remedies (§§ 257.97(d)(1-6)). These factors include: (1) extent and nature of 
Document submitted to conclude E.O.12866 Review

381

contamination; (2) reasonable probabilities of remedial technologies in achieving compliance 

with the groundwater protection standards; (3) availability of treatment or disposal capacity for 

CCR managed during implementation of the remedy; (4) potential risks to human health and the 

environment; (5) resource value of the aquifer; and (6) other relevant factors. EPA had included 

one additional factor in the proposal: “The desirability of utilizing technologies that are not 

currently available, but which may offer significant advantages over already available 

technologies in terms of effectiveness, reliability, safety, or ability to achieve remedial 

objectives.” EPA considered that this provision, which could be used to justify delaying 

remediation measures, was potentially subject to abuse and thus, inappropriate to be included in 

a self-implementing rule. 

For similar reasons, EPA deleted the provisions in the proposal, subsections (e) and (f) 

that would authorize a facility to determine that remediation of a release is not necessary. These 

sections which came from the MSWLF rule in part 258 are appropriate where there is state 

oversight. The preamble to the final MSWLF rule specifically discusses situation in which an 

approved State may decide not to require cleanup of hazardous constituents released to 

groundwater from a MSWLF (see 56 FR 51090). However, there is no similar guarantee that an 

individual facility will act in the public interest. 

8. Implementation of the Corrective Action Program

The proposed rule required the owner or operator to include a schedule for initiating the 

remedial activities in the schedule for implementing the remedy (§257.97(d)). The Agency 

understands that selecting a remedy is closely related to the assessment process and cannot be 

accomplished unless a sufficiently thorough evaluation of alternatives has been completed. The 

process of documenting the rationale for selecting a remedy requires that a report be placed in 
Document submitted to conclude E.O.12866 Review

382

the operating record that clearly defines the corrective action objectives and demonstrates why 

the selected remedy is anticipated to meet those objectives. The report must identify how the 

remedy will be protective of human health and the environment, attain the groundwater 

protection standards (either background or MCLs), attain source control objectives, and comply 

with waste management standards. 

The selection of a remedy also involves a public meeting with interested parties before 

finally selecting a remedy. For these reasons, the Agency is not establishing a deadline for 

completing the remedy selection process, but rather expects it to be completed as soon as 

practicable. Once the assessment of corrective measures has been completed within the 

timeframe specified in this rule, and the public meeting has occurred, the facility owner/operator 

must select a remedy and begin implementing that remedy as soon as is practicable. It is vitally 

important that the facility selects a remedy as soon as practicable and begins designing and 

implementing that remedy, so that releases to groundwater are addressed without unnecessary 

delay. EPA understands that there are a variety of activities that may be necessary in order to 

select the appropriate remedy (e.g., discussions with affected citizens, state and local 

governments; conducting on-site studies or pilot projects); and, once selected, to implement the 

remedy (e.g., securing on-site utilities if needed, obtaining any necessary permits, etc.). That is 

why EPA does not find it appropriate to set specific timeframes for selecting the remedy or to 

begin implementing the selected remedy. However, in order to ensure that the community is 

kept informed as to the progress of selecting and implementing the remedy, EPA is requiring that 
Document submitted to conclude E.O.12866 Review

383

the facility owner/operator, on a semiannual basis, post status reports/updates on their progress to 

their website and submit these to the state.117

However, the Agency has concluded that it is reasonable to require that once a remedy 

has been chosen, the owner or operator of the CCR unit must begin to implement that remedy 

within a specified period of time. Consistent with the timeframes throughout this section, the 

final rule requires that within 90 days of selecting a remedy, the owner or operator must have 

initiated corrective measures, including any interim measures determined to be appropriate, and 

have established a corrective action ground water monitoring program (and begin following it).

(§ 257.98). This is a reasonable timeframe in which to begin these activities based on EPA’s 

long experience in conducting and overseeing cleanup activities.

The remedy would be considered complete when the owner or operator demonstrates 

compliance with the groundwater protection standards for a period of three consecutive years,

and all other actions required to meet the performance standards in § 257.97(b) have been 

satisfied (e.g., source control). The owner or operator must obtain certification that the remedy 

is complete from a qualified professional engineer, and must notify the State Director. The 

certification must also be placed in the operating record and on the owner or operator’s internet 

site.

The Agency deleted the provision that allows an owner or operator to determine that 

compliance cannot be reasonably achieved with any currently available methods. The Agency 

determined that without state oversight or a permitting program, that provision was potentially 

 

117 As evidenced in 42 U.S. C. 6971(f), Congress intended that the OSHA be able to enforce its regulations to protect 

workers exposed to hazardous waste and that EPA and OSHA would work together to ensure that. EPA is clarifying 

that it intends that the CCR disposal rule not preempt applicable OSHA standards designed to protect workers 

exposed to CCRs; thus EPA’s final rule on CCR disposal will apply in addition to any applicable OSHA standards. 

The Agency has added specific regulatory language in this section to address this intent.
Document submitted to conclude E.O.12866 Review

384

subject to abuse and thus, inappropriate to be included in a self-implementing rule. 

9. Timing Overview

The groundwater monitoring regulations require that the owner or operator of existing 

CCR units must comply with § 257.90 - § 257.94 within 30 months of the date of publication of 

the rule. Essentially, that means that by the end of 30 months, the owner or operator must (1) 

install the groundwater monitoring system; (2) document the sampling and analysis procedures; 

(3) establish which statistical tests will be used to determine exceedances; (4) sample all wells to 

have a minimum of 8 samples for all Appendix III and IV parameters; and (5) determine if there 

is a statistically significant exceedance of any Appendix III parameter, which would trigger 

assessment monitoring.

New CCR units must comply with §§ 257.90-257.93, including the requirement under § 

257.94(b) to collect and analyze eight independent samples from each well for the parameters 

listed in Appendix III and IV to this part to determine background levels for all Appendix III 

and IV constituents, before commencing operation. Essentially, that means that before receiving 

CCR waste, the owner or operator must (1) install the groundwater monitoring system; (2) 

document the sampling and analysis procedures; (3) establish which statistical tests will be used 

to determine exceedances; and (4) sample all wells to have a minimum of eight samples for all 

Appendix III and IV parameters.

If assessment monitoring is triggered, within three months the owner or operator must 

sample all wells for all Appendix IV constituents (minimum of one sample) and resample 

(minimum of one sample) all wells for all Appendix III parameters and those Appendix IV 

constituents that were detected in the first round of sampling. The owner or operator could also 

simultaneously use this three-month timeframe to demonstrate that the statistically significant 
Document submitted to conclude E.O.12866 Review

385

increase found in detection monitoring was due to another source or sampling and analysis error. 

While conducting assessment monitoring, the owner or operator must continue sampling for all 

Appendix III constituents and any Appendix IV detected constituents semiannually. The owner 

or operator must sample for all Appendix IV constituents annually.

The owner or operator must also establish groundwater protection standards (MCL or 

background levels) for all Appendix IV constituents detected during sampling. 

If one or more Appendix IV constituents are detected at statistically significant levels 

above the groundwater protection standards established, or a release from a CCR unit has been 

detected, corrective action is triggered. The owner or operator must characterize the nature and 

extent of the release by installing additional monitoring wells, collecting data on the quantity and 

concentration levels of regulated constituents in the released material, sampling and notifying the 

State Director, local government officials, and any persons who own land or reside on the land 

that overlies the plume if the plume has migrated off site. The owner or operator must also place 

the notification in their operating record and website.

If corrective action is triggered, within three months the owner or operator must initiate 

an assessment of corrective measures. If the CCR unit is an unlined surface impoundment, the 

unit must also initiate closure or begin to retrofit the unit. The owner or operator could also 

simultaneously use these 3 months to demonstrate that the statistically significant increase found 

during assessment monitoring was due to another source or sampling and analysis error. 

The assessment of corrective measures must be completed in three months, with the 

possibility of an additional two months if the owner or operator demonstrates the need for 

additional time. The owner or operator must continue assessment monitoring and provide 

notification of the corrective measures assessment to the State Director and place the assessment 
Document submitted to conclude E.O.12866 Review

386

in the operating record and on the owner’s or operator’s website. The owner or operator also 

must discuss the results of the corrective measures assessment at least 1 month prior to selection 

of remedy in a public meeting.

Within three months of selecting a remedy, the owner or operator must initiate remedial 

activities. Corrective action is completed when the owner or operator demonstrates compliance 

with the groundwater protection standards for three consecutive years.

L. Closure of Inactive Units

As discussed in Unit VI.A, EPA proposed that inactive CCR surface impoundments that 

had not completed closure in accordance with specified standards by the effective date would be 

subject to all of the requirements applicable to existing CCR surface impoundments. EPA 

adopted this approach to create an incentive to expedite the closure of these units, with all of the 

significant risk mitigation that such a measure would entail. EPA is retaining this general 

approach in the final rule, but has revised the provision to grant inactive CCR surface 

impoundments more time to complete closure, consistent with the other closure provisions in the 

final rule. The final rule extends the deadline to three years from publication of the rule in the 

Federal Register.

The proposal was based on EPA’s belief that the time frames between publication of the 

final rule and the effective date would be sufficient for facilities to close inactive CCR surface 

impoundments. This was particularly true under the subtitle C option, where the time frame 

between publication and the effective date could be as long as 18 months, due to the need for 

subsequent action by authorized states. Under the proposed rule, the maximum amount of time a 

facility would have to initiate and complete closure of a disposal unit was seven months. 

However, as discussed elsewhere in this preamble, EPA received numerous comments raising 
Document submitted to conclude E.O.12866 Review

387

concern that these time frames would essentially be ‘‘impossible to meet’’ for surface

impoundments located in certain geographic and climatic conditions, as well as for all of the 

larger units. These comments convinced EPA that it had not adequately accounted for the 

complexities inherent in electric generating facility operations, and the different characteristics of 

CCR surface impoundments in designing the closure provisions in the proposal. EPA has 

revised the time frames applicable to closures in the final rule accordingly in light of these 

issues. See Unit VI.M below. These same considerations apply with respect to this provision, 

and additional time is therefore necessary to make this option truly viable. 

EPA selected three years based primarily on two factors. EPA initially focused on the 

minimum amount of time necessary to close a CCR surface impoundment. As discussed in more 

detail in Unit VI.M, there can be a substantial range in the amount of time needed to close a 

surface impoundment, depending on, for example, the size and location of the unit. 

However, a critical factor in EPA’s decision is that under this approach these units will 

not be subject to the rule’s groundwater monitoring or structural stability requirements (provided 

they complete closure within three years). Moreover, based on the information in the record, it 

appears highly unlikely that groundwater monitoring is currently being conducted at these units 

(as discussed in unit IV.A, the information on groundwater monitoring requirements applicable 

to existing units was extremely sparse, but many older units appear to lack effective groundwater 

monitoring systems). EPA considered that allowing these inactive units to remain in place 

without taking measures to address the continuing threat that these units present for a substantial 

amount of time could not be justified. EPA therefore focused on the amount of time authorized 

under the rule for implementation of the groundwater monitoring requirements (i.e., 2 years from 
Document submitted to conclude E.O.12866 Review

388

the effective date) and for key structural stability requirements (i.e., 18 months to complete key 

analyses).

As discussed in more detail in the next section, the information in the record 

demonstrates that it is feasible to complete the closure of CCR surface impoundments within 

three years. EPA recognizes that larger CCR surface impoundments (i.e., above 40 acres) may 

not be able to close within this time frame. However, to be able to support this provision, EPA 

must balance the risk mitigation achieved by closure of CCR surface impoundments against the 

risks inherent in allowing inactive CCR surface impoundments to remain in place for longer 

periods of time. The longer inactive CCR impoundments remain without all of the protections 

provided by the final rule, the greater the potential for significant health and environment 

impacts. Larger units are also the ones more likely to present the highest risks, and so warrant 

the greater oversight provided by application of all of the technical criteria to their operation (and 

closure). Consequently, EPA is unable to justify expanding this option to include the longer time 

frames available under §§ 257.102 or 257.103. 

The criteria for conducting the closure of inactive CCR surface impoundments are 

essentially the same as those applicable to active CCR units. Inactive units can either clean close 

units, or close with waste in place, subject to same performance standards in 257.102 for all 

other CCR units. If an inactive CCR surface impoundment is completely closed within the three 

year time frame, no other requirements apply to that unit. This means that no groundwater 

monitoring or other post-closure care requirements would apply to these units. Once an inactive 

CCR surface impoundment has been breached and dewatered, the risks are essentially the same 

as the risks associated with an inactive CCR landfill, which are not subject to any requirements 

under the final rule. 
Document submitted to conclude E.O.12866 Review

389

However, owners or operators of inactive CCR surface impoundments that have not 

completed closure within this time frame must comply with all of the requirements applicable to 

existing CCR impoundments. If the facility intends to maintain the inactive unit indefinitely,

whether to provide potential future capacity, or to continue to dredge the unit to provide material 

for beneficial use, or with the idea that it may be repurposed for other facility operations (e.g., to 

manage stormwater), there is no basis for distinguishing between these units and actively 

managed units on the basis of the potential risks. Thus, such units would need, for example, to 

meet all of the location and structural stability criteria (which could independently compel 

closure of the unit), install the groundwater monitoring system, and begin to monitor within the 

time frames established in the final rule. This also means that any facility that initiates closure 

under this provision but fails to complete it within this time frame, must comply with all 

groundwater monitoring requirements in §§257.90-98 (e.g., install groundwater monitoring 

wells) as well as all of the post-closure care requirements. 

M. Closure and Post-Closure Care

Closure and post-closure care are an integral part of the design and operation of CCR 

landfills and CCR surface impoundments.118 EPA solicited public comment on closure and postclosure care requirements under a subtitle D approach in the proposed rule and sought additional 

comment on specific closure requirements in a subsequent notice of data availability.

For CCR landfills, the proposed closure and post-closure care requirements were 

modeled on current regulations that apply to municipal solid waste landfills, which are codified 

in part 258. In some cases, the proposed requirements were modified to reflect the lack of a 

 

118

 As discussed in the proposed rule, EPA’s “Guide for Industrial Waste Management” documents the general 

consensus on the need for effective closure and post-closure care requirements (Chapter 11). This guide can be 

accessed at http://www.epa.gov/epawaste/nonhaz/industrial/guide/.
Document submitted to conclude E.O.12866 Review

390

mandatory permitting mechanism (see Unit V.A. of this preamble for additional information), in 

addition to other changes EPA believed were appropriate to ensure that there would be no 

reasonable probability of adverse effects from the wastes that remain after a CCR unit had 

closed. For CCR surface impoundments, the Agency modeled the proposed requirements on 

current regulations that apply to interim status hazardous waste surface impoundments, which 

are codified in part 265. Some additional proposed provisions were based on requirements 

currently applicable to water, sediment or slurry impoundments and impounding structures that 

are regulated by the Mine Safety and Health Administration (MSHA) of the U.S. Department of 

Labor. See 30 CFR part 77, subpart C.

The proposed rule included a number of closure and post-closure criteria, 

including: (1) requirements to prepare closure and post-closure plans; (2) requirements for 

conducting closure of a CCR unit when the CCR is removed and when the CCR is left in place, 

including design criteria for a final cover system; (3) timeframes to commence and complete 

closure activities; (4) closure and post-closure care certification requirements; and (5) 

requirements for conducting post-closure care. The Agency received numerous comments on the 

proposed closure and post-closure criteria, with the majority of comments pertaining to the 

proposed timeframes for closure (i.e., timeframes for commencing and completing closure) of a 

CCR surface impoundment. As a result of these comments, EPA solicited additional comments 

on the timeframes for closure in a NODA published on August 2, 2013 (NODA 3). See 78 FR at 

46944. The sections below explain the approach and rationale for the final rule closure and postclosure care criteria based on the comments received in response to the proposed rule and the 

NODA.

1. Closure Plan
Document submitted to conclude E.O.12866 Review

391

The Agency proposed to require that the owners or operators of CCR landfills and 

CCR surface impoundments prepare a written closure plan describing the closure of the unit and 

providing a schedule for implementation of the plan. 75 FR at 35207-08. The closure plan 

would describe the steps necessary to close the CCR unit at any point during the active life based 

on recognized and generally accepted good engineering practices. The proposal also identified 

the minimum information necessary to include in the closure plan. This information included: 

(1) an estimate of the largest area of the CCR unit that would ever require a final cover during 

the active life of the CCR unit; (2) an estimate of the maximum inventory of CCR that would 

ever be present on-site over the active life of the CCR unit; (3) a description of the final cover 

and the procedures to be used to install the final cover; (4) a description of how the facility will 

provide for major slope stability following closure; (5) a description of the measures the owner 

or operate will adopt to preclude the probability of future impoundment of water, sediment, or 

slurry; and (6) a schedule for the implementation of the closure plan. See proposed §257.100(a) 

and (g). The proposed rule would also have required each owner or operator to develop the 

closure plan by the effective date of the final rule. Finally, EPA proposed to require the owner or 

operator to have the closure plan certified by an independent registered professional engineer, in 

addition to complying with all of the notification and posting requirements under the rule.

EPA received few public comments on either the proposal to develop a closure 

plan or the individual elements of the closure plan. Some commenters generally supported the 

requirement for an owner or operator to develop a closure plan for the CCR unit, and no 

commenters opposed it. However, one commenter requested that EPA include more specific 

requirements for slope stability in the regulatory language beyond the general requirement to 

address major slope stability in the closure plan for units that close with waste in place.
Document submitted to conclude E.O.12866 Review

392

The Agency agrees that the proposed regulatory language should provide more specific 

criteria defining the expectations with regard to major slope stability. The proposed regulation 

merely required the owner or operator to “provide for major slope stability” in the closure plan, 

or in other words, to include measures to ensure that slope stability issues will be accounted for 

in designing the final cover. See 75 FR 35252. 

EPA explained that unit closure must provide for major slope stability to prevent the 

sloughing of the cover system over the wastes that will remain in the CCR unit over the long 

term. Sloughing of a land slope can occur when the earth material becomes saturated with water 

and incapable of maintaining the slope resulting in the movement or sliding of the earth material. 

75 FR at 35209. Slope stability is a critical issue in the design of final cover systems for both 

surface impoundments and landfills because cover system slope instability has been attributed to 

a number of final cover system failures.119 More specifically, the primary causes of final cover 

system slope failure during construction have been identified as: (1) placing soil over the 

sideslope geosynthetics from the top of the slop downward, rather than the toe of the slope 

upward; (2) using presumed values for critical interface shear strengths that were not 

conservative; and (3) using interface shear strength values from laboratory tests performed under 

conditions not representative of the actual field conditions. For final cover system slope failures 

after rainfall or thaw, the primary causes of failure have been identified as: (1) not accounting for 

seepage forces; (2) clogging of the internal drainage layer, which leads to increased seepage 

forces; and (3) not accounting for moisture at the geomembrane and compacted clay liner 

interface (which weakened the interface) due to both rain falling on the compacted clay liner 

 

119

 USEPA, “Assessment and Recommendations for Improving the Performance of Waste Containment Systems,” 

EPA/600/R-02/099, December 2002.
Document submitted to conclude E.O.12866 Review

393

surface during construction and freeze-thaw effects. 

Given that slope stability is a critical issue in the design and eventual performance of a 

final cover system, EPA has adopted a new criterion in the performance standard that all closures 

must meet: the owner or operator must ensure that the CCR unit is closed in a manner that will 

“provide for major slope stability to prevent the sloughing or movement of the final cover system 

during closure and throughout the post-closure care period.” See § 257.102(d)(1)(iii). Or in 

other words, the owner or operator must design a final cover system with any measures 

necessary to ensure that the major slopes of the closed CCR unit remain stable. Consistent with 

the proposal, the closure plan must discuss how the final cover system will achieve the 

performance standards specified in the regulation, which will necessarily include how the 

measures taken to address major slope stability. As explained in the proposed rule, the original 

provision was based on existing MSHA standards, specifically the requirements under 30 CFR 

§77.216-5 which apply to abandoned water, sediment or slurry impoundments and impounding 

structures.120 75 FR 35208-09. Under these requirements major slope stability includes long 

term stability considerations, such as “erosion control, drainage, etc.” These issues are equally 

relevant to the closure of CCR units, and EPA expects facilities to account for these factors in 

their final closure plans. 

The remaining information elements of the closure plan have been adopted without 

revision (although EPA has reorganized the final regulatory text for greater clarity). These are 

briefly summarized below:

a. An estimate of the largest area of the CCR unit ever requiring a final cover during 

 

120

 The term “abandoned” is defined in the MSHA regulations under 30 CFR §77.217, and as applied to an 

impoundment or impounding structure such term means that work on the structure has been completed in 

accordance with a plan for abandonment approved by the District Manager.
Document submitted to conclude E.O.12866 Review

394

the active life of the CCR unit. If the owner or operator routinely closes portions of a CCR unit 

as the design capacity is reached, the closure plan should indicate the largest area of the CCR 

unit that will be open (and requiring a final cover) at one time.

b. An estimate of the maximum inventory of CCR ever on-site over the active life of 

the CCR unit. If the owner or operator routinely closes portions of a CCR unit as the design 

capacity is reached, the closure plan should indicate the maximum inventory of CCR that will be 

open (and requiring a final cover) at one time.

c. A description of the final cover and the procedures to be used to install the final 

cover. The closure plan should also discuss how the closure performance standard will be 

achieved.

d. A description of the provisions to preclude the probability of future impoundment 

of water, sediment, or slurry. The final grades of the final cover system should promote surface 

water run-off and minimize erosion. The closure plan should also discuss the steepness of the 

slopes of the final cover system, in addition to the vertical spacing and width of benches.

e. A schedule for the implementation of the closure plan.

This rule also provides new procedures for amending an existing written closure 

plan. While the proposed rule did not specifically allow or require the owner or operator to 

revise an existing closure plan, EPA recognizes that available information and conditions known 

at the time the closure plan is prepared may very well change during the active life of the CCR 

unit, which could be decades in some cases. In order to eliminate any potential confusion over 

whether an owner or operator is allowed under this rule to revise the closure plan to reflect a 

change in conditions or circumstances, the final rule adopts new procedures for amending a 

written closure plan. These new procedures allow the owner or operator to revise the closure 
Document submitted to conclude E.O.12866 Review

395

plan at any time provided the revised plan is placed in the facility’s operating record, in addition 

to complying with all of the notification and posting requirements under the rule. Furthermore, 

the final rule requires the closure plan be amended any time there is a change in conditions that 

would substantially affect the written closure plan in effect.

Finally, in a departure from the proposed rule, the final rule provides owners and 

operators one year from the rule’s effective date to prepare the initial written closure plan, which 

is one year longer than proposed. EPA made this change as part of its effort to coordinate the 

compliance and implementation timeframes in the CCR rule with another Agency rulemaking –

the Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating Point 

Source Category (ELG) rulemaking – that may affect owners and operators of CCR units. See 

78 FR 34442. As explained in that proposal, consistent with RCRA section 1006(b), EPA has 

sought to effectively coordinate any final RCRA requirements with the ELG requirements, to 

minimize the overall complexity of these two regulatory structures, and to facilitate the 

implementation of engineering, financial and permitting activities. EPA’s goal is to ensure that 

the two rules work together to effectively address the discharge of pollutants from steam electric 

generating facilities and the human health and environmental risks associated with the disposal 

of CCRs, without creating avoidable or unnecessary burdens.

EPA proposed to require facilities to complete a closure plan by the rule’s effective date, 

or six months following the rule’s publication. However, this would have required owners or 

operators to prepare closure plans approximately three months prior to publication of the ELG 

final rule. Given that an understanding of the ELG rule would likely affect the details and 

content of a closure plan, the Agency concluded that it would make no sense to requiring an 

owner or operator to prepare a closure plan within six months, only to have them update it 
Document submitted to conclude E.O.12866 Review

396

months later, after the owner or operator understands the requirements of both the CCR and ELG 

final rules. No measureable environmental or health benefit would be gained by having a closure 

plan in place for those three months. Moreover, EPA wants to ensure that closure plans are well 

considered, and the knowledge that a plan may need to be substantially revised in the near future 

could create a contrary incentive.

By extending the deadline for preparation of the closure plan by one year, owner or 

operators will have slightly more than six months after the ELG rule is published to complete a 

closure plan. This is consistent with the six month timeframe EPA originally proposed, which as 

noted, would have required completion of the closure plan within six months of publication of 

the final CCR rule.

2. Closure of a CCR Unit through Removal and Decontamination

The proposed rule would have allowed facilities to close a CCR unit either through CCR 

removal and decontamination of all areas affected by releases from the CCR unit (“clean 

closure”) or with CCR in place with a final cover system. The Agency proposed that if the 

owner or operator elects to clean close a CCR unit, CCR removal and decontamination are 

complete when constituent concentrations throughout the CCR unit and any areas affected by 

releases from the CCR unit do not exceed the numeric cleanup levels for those constituents 

found in CCR established by the state in which the CCR unit is located, to the extent that the 

state has established cleanup levels. 75 FR 35208. In the absence of state cleanup levels, the 

proposal stated that metals should be removed to either statistically equivalent background 

levels, or to maximum contaminant levels or health-based numbers. Once a facility had 

completed clean closure of a CCR unit, EPA proposed that post-closure care would not be 

required for that unit. EPA also noted that it was considering whether to adopt a further 
Document submitted to conclude E.O.12866 Review

397

incentive for clean closure, under which the owner or operator could remove the deed notation 

required under the proposed rule, once all CCR has been removed from the facility and 

notification provided to the state.

Several commenters urged that EPA not require clean closure as the only method 

of closing a CCR unit, arguing that clean closure is not feasible or not necessary. Others 

acknowledged that clean closure is not only a viable option for their CCR units, but in some 

cases it would be “the only prudent closure option.” A few commenters suggested criteria to 

determine the conditions under which clean closure would be appropriate. For example, one 

commenter agreed with EPA that the risk-based corrective action process (RBCA) would be 

useful in determining whether waste removal is appropriate at the site. 

EPA received relatively few comments on the specific standards for conducting clean 

closure. One commenter identified six criteria that should be included in any final regulation in 

order to allow a facility to have been deemed to have completed clean closure of a CCR surface 

impoundment and thereby avoid post–closure care. Some of the commenter’s suggestions were 

comparable to requirements in the proposal. However the commenter also included 

requirements to ensure that adequate engineering controls were used to prevent contamination of 

soil and groundwater during excavation, and requirements for quarterly monitoring of shallow 

groundwater beneath the surface impoundment for a period of 5 years to demonstrate that no 

residual CCR was left in place. Finally, a number of commenters supported a provision that 

would allow the owner or operator to remove the deed notation required provided all CCR is 

removed from the site.

EPA did not propose to require clean closure nor to establish restrictions on the situations 

in which clean closure would be appropriate. As EPA acknowledged in the proposal, most 
Document submitted to conclude E.O.12866 Review

398

facilities will likely not clean close their CCR units given the expense and difficulty of such an 

operation. Because clean closure is generally preferable from the standpoint of land re-use and 

redevelopment, EPA has explicitly identified this as an acceptable means of closing a CCR unit. 

However, both methods of closure (i.e., clean closure and closure with waste in place) can be 

equally protective, provided they are conducted properly. Thus, consistent with the proposal, the 

final rule allows the owner or operator to determine whether clean closure or closure with the 

waste in place is appropriate for their particular unit. EPA agrees that the RBCA process, using 

recognized and generally accepted good engineering practices such as the ASTM Ec0–RBCA 

process, can be a useful tool to evaluate whether waste removal is appropriate at the site. It is, 

however, not a necessary prerequisite. 

EPA has adopted the provisions governing clean closure from the proposed rule with 

only one revision. The final provisions consist of two performance standards: First, the owner or 

operate must remove all CCR from the unit and decontaminate all areas affected by releases 

from the CCR landfill or surface impoundment. As part of meeting this performance standard, 

the final rule requires facility owners/operators to remove all wastes from the closing unit, and 

remove all liners contaminated with CCR waste and CCR waste leachate. The final rule also 

requires the owner or operator to remove and decontaminate all areas affected by releases from 

the CCR unit. This would require removal or decontamination of the underlying and 

surrounding soils and flushing, pumping, and/or treating the aquifer. The Agency interprets the 

term ‘soil’ broadly to include both unsaturated soils and soils containing groundwater.

Second, the final rule specifies that closure has been completed when all CCR in the unit 

and any areas affected by releases from the CCR unit have been removed and groundwater 

monitoring demonstrates that all concentrations of the assessment monitoring constituents listed 
Document submitted to conclude E.O.12866 Review

399

in Appendix IV to part 257 do not exceed either statistically equivalent background levels or 

MCLs. This standard encompasses both saturated and unsaturated soils, as well as the 

groundwater. As part of attaining this standard, facility owners and operators will need to 

document that any contaminants left in the subsoils (i.e., contaminated groundwater left in soils 

below the former landfill or impoundment) will not impact any environmental media including 

groundwater, surface water, or the atmosphere in excess of Agency-recommended limits or 

factors. Typically, any metals in these “subsoils” in excess of background levels are allowed to 

either naturally attenuate, or are removed by flushing. Once the facility has removed all of the 

assessment monitoring constituents listed in Appendix IV down to background levels or MCLs 

the groundwater is considered to be “clean” and closure is complete. 

EPA disagrees that specific provisions requiring the use of adequate engineering controls 

to prevent contamination of soil and groundwater during excavation are necessary to ensure that 

closure will be protective. To the extent that any contamination of soil or groundwater has 

occurred during CCR removal, this would constitute a release (or an “area affected by a release”) 

from the CCR unit, and the final performance standard requires the facility to ensure that this 

been removed before closure is deemed to be complete. 

Contrary to the commenter’s suggestion that quarterly monitoring for 5 years is necessary 

to demonstrate that no residual CCR was left in place, the rule requires a facility to document 

that all Appendix IV concentrations are below MCL or background levels for two consecutive 

sampling events, using the statistical procedures in § 257.93(g). This is the same sampling 

required to demonstrate under the groundwater monitoring program that there is no longer a 

reason to suspect a source of contamination, and that consequently assessment monitoring can 

cease. EPA selected these provisions as the most factually analogous to the circumstances 
Document submitted to conclude E.O.12866 Review

400

surrounding the clean closure of a CCR unit. Once a facility has removed the waste and any 

liner, the presumption is that the source of contamination has been removed as well. Although 

there may be site-specific factors that could support the need for a longer monitoring period, 

there is no factual basis to require a longer minimum period of sampling on a national basis. 

This represents a change from the proposal. EPA proposed a performance standard that 

required decontamination to either any state established numeric cleanup levels for CCR 

constituents, or in the absence of state cleanup levels, the removal of metals to either statistically 

equivalent background levels, or to maximum contaminant levels (MCLs), or health-based 

numbers. This was taken directly from the current part 258 standards for municipal solid waste 

landfills. EPA has deleted both of these standards as inappropriate for these units. 

The reference to state established clean up levels was inadvertently carried over from the 

existing part 258 regulations. As explained throughout this preamble, EPA is unable to rely on 

state programs to establish the specific standards under this rule; the record does not contain 

information on all state cleanup standards, and there is no mechanism for states to operate 

approved programs in lieu of federal programs. 

EPA determined that the requirement to clean all soils to background levels was equally 

inappropriate. In practice, EPA does not routinely require complete removal of all 

contamination (that is, cleanup to ‘background’) from a closing unit even for hazardous waste 

units. Requiring CCR units to clean up soils to levels before the site was contaminated, would 

be more stringent than current hazardous waste policies. There is no basis in the current record 

to impose provisions for the remediation of CCR units that are more stringent than those 

imposed on hazardous wastes. 
Document submitted to conclude E.O.12866 Review

401

Upon completion, the unit is exempt from the ground water monitoring and any other postclosure care requirements. In addition, the final rule adopts the proposal to allow the owner or 

operator to remove the deed notation required under §257.102(i)(4), upon certification that clean 

closure has been completed. EPA had proposed this option to create a further incentive for clean 

closure, and it is clear from the commenters, who uniformly supported this option, that it does so. 

EPA had proposed this option to create a further incentive for clean closure, and it is clear from 

the comments received in response that it will create a strong incentive for clean closure. Some 

commenters raised concern about the effect this option will have on state laws, which may not 

allow the deed notation to be removed. EPA notes that these criteria do not preempt state 

laws; to the extent state law requires the facility to retain a deed notation despite the completion 

of clean closure, those requirements will remain in place, notwithstanding this final rule.

3. Closure of a CCR Unit with CCR in Place

The proposed rule would have also allowed facilities to close a CCR unit by 

leaving the CCR in place and installing a final cover system. The final cover system would have 

been required to be designed and constructed to a have a permeability less than or equal to the 

permeability of any bottom liner system or the natural subsoils present, or a permeability no 

greater than 1x10-5centimeters per second (cm/sec), whichever is less. The proposal would have 

also required an infiltration layer that contains a minimum of 18 inches of earthen material and 

an erosion layer containing a minimum of 6 inches of earthen material that is capable of 

sustaining native plant growth to help minimize erosion of the final cover. These proposed 

requirements were generally modeled after the performance standard and technical requirements 

contained in §258.60 for municipal solid waste landfills. 75 FR 35208. EPA also proposed that 

the final cover system would have to be designed to minimize the disruption of the final cover 
Document submitted to conclude E.O.12866 Review

402

through a design that accommodates settling and subsidence and provides for major slope 

stability to prevent the sloughing of the closed CCR unit over the long term. These last two 

criteria are based on existing requirements for interim status units under RCRA part 265 and 

MSHA requirements under 30 CFR part 77, subpart C, respectively.

As proposed, CCR surface impoundments would have been subject to an 

additional set of performance standards. The owner or operator of a CCR surface impoundment 

would have been required to either drain the CCR unit or solidify the remaining wastes. In 

addition, the owner or operator would have been required to stabilize the wastes to a bearing 

capacity to support the final cover. The proposed criteria would also have required that the final 

cover for all CCR units be designed to minimize the migration of liquids through the closed CCR 

surface impoundment over the long term; promote drainage, and accommodate settling and 

subsidence so that the final cover’s integrity is maintained. Finally, closure of the CCR unit 

would also have been subject to the general performance standard that the probability of future 

impoundment of water, sediment, or slurry be precluded.

The Agency also proposed to allow owners or operators of CCR units to select an 

alternative final cover design. As proposed, the alternative final cover design would have 

required an infiltration layer that achieves an equivalent reduction in infiltration, and an erosion 

layer that would provide equivalent protection from wind and water erosion, as the infiltration 

and erosion layers specified for final covers described above. In addition, the proposed approach 

for alternative final cover designs would have also required certification by an independent 

registered engineer, notification being provided to the state that the alternative final cover design 

has been placed in the facility’s operating record, and placement of the alternative final cover 

design on the owner or operator’s publicly accessible internet site.
Document submitted to conclude E.O.12866 Review

403

a. Final Cover System Design

EPA received comments supporting the proposed approach, while other 

commenters opposed the proposed final cover system design requirements. One state 

commenter generally supported using the part 258 final cover design requirements as a general 

model for CCR units. This commenter also requested that the Agency clarify whether new CCR 

units would be required to install a composite final cover system given that it was proposed that 

new CCR units would be required to designed and constructed with a composite bottom liner. 

Another state indicated that its state regulations allow final cover designs similar to that proposed 

by EPA, although the state requires a 24 inch infiltration layer and a 12 inch erosion layer. 

Another state referenced current research showing that soil-only covers may not be effective in 

minimizing infiltration over the long term under certain climates. This commenter 

recommended that a geomembrane should be made a standard component of the cover system. 

Other commenters stated that the final cover system should be a composite system consisting of

a synthetic component and a low permeability clay component. A state commenter offered that 

post-closure maintenance of composite cap system incorporating a geomembrane has been 

challenging in that state. Another commenter stated that a compacted clay liner should not be 

used as a final cover for landfills due to the potential for settlement cracking, desiccation 

cracking, and root and animal penetration. Instead, it was suggested that if a single barrier 

system is used, then a benefit-cost analysis favors a geomembrane, and if a composite barrier is 

to be used, a benefit-cost analysis favors a composite system of a geomembrane and 

geosynthetics clay liner.

The Agency also received many comments on the proposed approach to allow the 

use of alternative final cover systems. Most commenters supported allowing the use of 
Document submitted to conclude E.O.12866 Review

404

alternative covers. One commenter stated that the use of geosynthetic clay liners in lieu of 18 

inches of earthen material for the infiltration layer is a commonly accepted for cover systems for 

municipal solid waste landfills. This commenter also noted that that geosynthetic clay liners 

have documented permeability characteristics on the order of 1 x 10-9cm/sec. Another 

commenter supported allowing the use of alternative cover systems because a one-size-fits-all 

approach is not appropriate for final cover system designs. A state also offered that 

appropriately designed alternative final covers such as capillary barrier covers and 

evapotranspiration covers are being successfully used at facilities in the state.

After considering comments received regarding final covers, the Agency is 

essentially finalizing the approach in the proposed rule with minor revisions. The final rule 

allows owners or operators to use a final cover system consisting of an infiltration layer and an 

erosion layer, provided the infiltration layer has a permeability less than or equal to the bottom 

liner or natural subsoils. However, regardless of the bottom liner or natural subsoils present, the 

final cover must have a permeability no greater than 1 x 10-5cm/sec.

To address the commenters’ concerns that the final cover system may not function 

effectively as designed over the long term under certain circumstances, the rule also includes a 

performance standard that the any final cover system must meet. This standard is modeled after 

the closure performance standard applicable to interim status hazardous waste units under 

§265.111. The final rule requires that any final cover system control, minimize or eliminate, to 

the maximum extent practicable, post-closure infiltration of liquids into the waste and releases of 

leachate (in addition to CCR or contaminated run-off) to the ground or surface waters. Thus, a 

facility must ensure that in designing a final cover for a CCR unit they account for any condition 

that may cause the final cover system not to perform as designed. This could include accounting 
Document submitted to conclude E.O.12866 Review

405

for site conditions that may increase the likelihood that a cover would be susceptible to 

desiccation cracking or settlement cracking. Under this performance standard, if the cover 

system results in liquids infiltration or releases of leachate from the CCR unit, the final cover 

would not be an appropriate cover. The final rule requires the final cover system design to be 

certified by a qualified professional engineer that the design meets both the performance 

standard and cover system criteria.

The final rule does not require the use of composite final covers, such as a 

geomembrane underlain by a compacted soil infiltration layer. This is also the case in situations 

for a CCR unit that is designed with a composite bottom liner or if the permeability of the soil 

underlying the unit is comparable to the permeability of a geomembrane. As EPA has concluded 

for municipal solid waste landfills, in certain site-specific situations it may be possible to 

construct an infiltration layer that achieves an equivalent reduction in infiltration without 

matching the permeability in the bottom liner material. 62 FR 40710. 

Nonetheless, in certain locations, composite cover systems may be necessary to 

achieve the rule’s performance standards. EPA acknowledges that under certain circumstances 

issues can arise with compacted clay barriers, particularly when used alone. These can include 

desiccation, freeze-thaw sensitivity, and distortion due to total and differential settlement of the 

underlying wastes. These issues can generally be addressed through proper maintenance of the 

cover system; and in fact the final rule requires as part of post-closure care that the owner or 

operator maintain the integrity and effectiveness of any final cover, including making repairs to 

the final cover to correct the effects of settlement, subsidence, erosion, or other events, and 

preventing run-on and run-off from eroding or otherwise damaging the final cover. 

Consequently EPA is not mandating the installation of a composite liner system.
Document submitted to conclude E.O.12866 Review

406

However, fewer problems are typically seen with the use of composite cover systems. 

And while ongoing oversight and proper maintenance is necessary to ensure the efficacy of any 

cover system, less effort is generally involved to ensure the continued performance of a 

composite cover system. EPA therefore generally recommends that facilities install a composite 

cover system, rather than a compacted clay barrier, as the composite system has often proven to 

be more effective (and cost effective) over the long term. For these reasons, EPA also 

anticipates that composite cover systems will be recommended in many circumstances by 

qualified Professional Engineers.

The final rule also allows the use of an alternative final cover. The rule requires 

that the alternative final cover must include infiltration and erosion layer that achieve equivalent 

performance as the minimum designs specified for final cover systems as discussed above. As 

discussed in the proposed rule, EPA included this provision to increase the flexibility for an 

owner or operator of a CCR unit to account for site-specific conditions. Moreover, these 

provisions will provide an opportunity to incorporate future technology improvements that 

would be missed if the rule required prescriptive design measures. In addition, these 

requirements would not supersede more stringent state requirements. Thus, if a state either has 

more prescriptive or more stringent standards in its state regulations applicable to CCR units, 

those state requirements would control any final cover system or alternative final cover system 

design.

While the rule provides the owner or operator flexibility in selecting the final 

cover for the unit, EPA remains concerned about the lack of guaranteed state oversight on final 

cover selection. A final cover system that does not perform as designed may result in 

unacceptable infiltration of water into the closed CCR unit that may lead to leachate and releases 
Document submitted to conclude E.O.12866 Review

407

from the unit. To address this concern, as well as the concerns raised by commenters regarding 

the long-term performance of certain cover systems by providing further assurance that the final 

cover system will perform over the long term, EPA has deleted the proposed provision that 

would have allowed owners or operators to shorten the length of the post-closure care period. As 

discussed in Unit M.9 below, the final rule requires facilities to conduct post-closure care for all 

CCR units for 30 years.

b. Performance Standards When Leaving CCR in Place

EPA received no significant comments on the proposed performance standards. 

The Agency is therefore finalizing these requirements without revision from the proposal 

(although EPA has reorganized the final regulatory text for greater clarity). The performance 

standards are summarized below:

i. As discussed in the previous section, the CCR unit must be closed in a manner 

that will control, minimize or eliminate, to the maximum extent practicable, post-closure 

infiltration of liquids into the waste and releases of CCR, leachate, or contaminated run-off to the 

ground or surface waters.

ii. The CCR unit must be closed in a manner that will preclude the probability of 

future impoundment of water, sediment, or slurry.

iii. The CCR unit must be closed in a manner that will provide for major slope 

stability, which is discussed is Unit M.1 for closure plans above.

iv. The CCR unit must be closed in a manner that will minimize the need for further 

maintenance of the unit.

v. The CCR unit must be closed in the shortest amount of time consistent with 

recognized and generally accepted good engineering practices. The Agency added this 
Document submitted to conclude E.O.12866 Review

408

performance standard to be consistent with the final provisions applicable for the timeframes for 

initiating and completing the closure of CCR units.

4. Timeframes for Closure

The Agency proposed that closure of a CCR landfill or CCR surface 

impoundment must be initiated by the owner or operator no later than 30 days following the 

known final receipt of CCR. To address concerns about “inactive” or abandoned units, the 

proposed rule also provided that a CCR unit must initiate closure no later than one year after the 

most recent receipt of CCRs if the CCR unit had remaining capacity and there was a reasonable 

likelihood that the CCR unit would receive additional CCR (i.e., the rule would have forced the 

facility to close the CCR unit). See 77 FR at 35209 and proposed §257.100(j). In addition, the 

proposed rule would have required an owner or operator to complete closure activities within 

180 days of initiating closure. See proposed §257.100(k). Thus, the maximum amount of time a 

facility would have had to initiate and complete closure of a CCR unit was seven months.

While the existing closure criteria for municipal solid waste landfills allow the Director 

of an approved State to grant time extensions for closure (both to initiate and to complete 

closure) if steps are taken to prevent threats to human health and the environment from the 

unclosed unit, EPA proposed not to include similar provisions for owners or operators of CCR 

units. At proposal, the Agency believed that extending the closure deadlines was inappropriate 

because, in the absence of an approved State program, the owner or operator could unilaterally 

decide to extend the time for closure of a CCR unit, without any basis, or oversight by a 

regulatory authority. 75 FR 35209.

EPA received numerous comments in response to the proposed deadlines under the 

subtitle D proposed approach. Industry and state commenters stated that the proposed deadlines 
Document submitted to conclude E.O.12866 Review

409

to begin and complete closure activities (30 and 180 days, respectively) are technically 

impracticable and simply too short for the vast majority of CCR units, especially for CCR 

surface impoundments to complete closure. Commenters stated that a 30-day deadline to initiate 

closure activities may not be workable in situations such as when there are construction 

limitations due to seasonal or climatic conditions, and should not be required in circumstances 

when a coal-fired generating unit is temporarily idled (e.g., maintenance related outages or an 

outage corresponding with a CCR handling system conversion). Regarding the amount of time 

needed to close a unit, numerous commenters noted that it would be impossible to properly 

complete closure activities within the proposed 180 days at most surface impoundments due to 

the length of time needed to dewater an impoundment and stabilize the wastes prior to 

constructing the final cover system. For example, commenters pointed out that dewatering of a 

surface impoundment alone can take several years to complete because impoundments can be 

hundreds of acres in size. One commenter provided information related to an ongoing CCR 

surface impoundment closure where the dewatering and ash stabilizing phases of closure took 

two years to complete. Commenters also stated that because a large number of CCR disposal 

units will have to be closed during roughly the same timeframe, facilities may not be able to 

obtain the necessary specialized personnel, equipment, and materials (e.g., clay or fill material, 

liner materials) to close multiple units simultaneously. This issue may be further complicated in 

locations where multiple facilities are competing for the same limited resources. Commenters 

further argued that adopting the same closure deadlines applicable to municipal solid waste 

landfills is not appropriate given differences in size, design, and operation (e.g., CCR surface 

impoundments contain large volumes of water, municipal solid waste landfills typically close 

each component cell when it reaches its disposal capacity). As a result of these concerns, 
Document submitted to conclude E.O.12866 Review

410

commenters recommended that EPA extend the deadlines both to commence and complete 

closure activities. The majority of the these commenters, however, urged EPA not to establish 

specific deadlines for closure and instead require facilities to close a CCR unit consistent with a 

closure plan approved by a state, or developed and certified by a qualified professional, such as a 

professional engineer.

In a subsequent NODA, the Agency solicited additional public comment on 

several different options to address these concerns. 78 FR at 46944-46. With respect to the 

deadline to initiate closure, EPA presented several examples of routine and legitimate 

circumstances in which CCR units would not receive CCR for periods longer than one year, even 

though the facility intended to continue to use the unit. For example, EPA discussed 

circumstances in which the facility alternates between two surface impoundments, only one of 

which is operational at a time. Once the impoundment has reached capacity, the facility 

dewaters the unit, and begins to send CCR to the second impoundment. Once the unit is 

dewatered, the CCR is excavated and disposed in an adjacent landfill. The time to fill these units 

has varied over the years as demand has fluctuated, but a typical time to fill a unit with CCR is 

two years, perhaps longer, during which the other unit is “idle,” in that it does not “receive 

CCR,” but it remains operational.

The Agency also solicited comment on a revised approach to the deadline to initiate 

closure. The approach entailed establishing a rebuttable presumption that if the CCR unit has not 

received waste within a particular period of time (e.g., 18-24 months), the CCR unit would be 

considered inactive and unit closure would be required to begin within a specified time. 

However, if the facility could substantiate that there was a reasonable likelihood that the CCR 

unit would again receive CCR in the future and also was able to document certain findings, the 
Document submitted to conclude E.O.12866 Review

411

owner or operator would not need to immediately commence closure of the CCR unit. In the 

NODA EPA discussed several examples of situations that could support a demonstration that 

immediate closure of the CCR unit was not necessary. One example was if an owner or operator 

could document that a CCR unit had been dedicated to a temporarily idled coal-fired generating 

unit and there is a reasonable likelihood that CCRs will be disposed in the CCR unit once the 

coal-fired generating unit resumes operation. Another situation presented was a CCR unit 

dedicated to a coal-fired generating unit that was not burning coal at the time (e.g., electricity 

was being generated with other fuels such as natural gas), but the facility needed the CCR unit 

following resumption of coal burning. A final example involved normal facility operations that 

include periods during which the CCR unit does not receive CCR for extended periods (e.g., the 

alternating use of two CCR surface impoundments discussed above). As part of this approach, 

the Agency solicited comment on whether to limit the length of time an owner or operator can 

maintain an idle CCR unit.

With respect to the deadline for completing closure, EPA acknowledged in the NODA 

that different deadlines, at least for the larger CCR units, were warranted. Information that the 

Agency has obtained throughout the rulemaking confirmed commenters’ claims that the 

timeframes originally proposed to complete closure of CCR surface impoundments will be 

practicably infeasible for the larger impoundments. However, the Agency cautioned that any 

ultimate timeframe provided in the rule that would be practicable for the largest CCR units 

would be far too long to justify as timeframes for closure of the smaller impoundments. EPA 

explained that it intended to examine available closure plans for CCR surface impoundments to 

determine whether there are consistent timeframes or other factors that EPA could adopt as part 

of the regulations. EPA specifically identified two closure plans of CCR units that were 
Document submitted to conclude E.O.12866 Review

412

scheduled to close as a possible source of useful information. These plans projected that closure 

would take multiple years to complete for modestly-sized CCR surface impoundments (i.e., less 

than 50 acres). 

a. Deadlines to Initiate Closure

In response to the NODA, most utility commenters stated that the time to initiate 

closure should be tied to reasonable triggers that account for the diverse uses of CCR surface 

impoundments and CCR landfills. In particular, these commenters recommended that closure 

not be initiated for an idled CCR unit if the CCR unit is expected to receive additional waste in 

the future, whether CCR or any other waste the unit may be authorized to manage. These 

commenters also supported the scenarios EPA described in the NODA as examples of legitimate 

situations that could warrant delaying the immediate closure of a CCR unit. Many of these 

commenters generally agreed that the rebuttable presumption alternative discussed in the NODA 

could be an appropriate approach for closure, in particular for CCR units not covered by a stateapproved operating plan, provided the regulatory approach would be implemented in a manner 

that did not restrict other legitimate uses of the CCR unit. Many of these commenters also 

asserted that a limit on the length of time a CCR unit can remain idle is not practical because the 

owner or operator will not be able to predict with any degree of certainty how long a CCR unit 

will be idled. Several of these commenters also urged EPA to specify in the final rule what EPA 

intended by the phrase “initiation of closure;” that is, that EPA define the activities or actions the 

owner or operator must take by the deadlines specified in the rule.

A trade organization and other commenters warned that strict restraints on the initiation 

(and completion) of closure of CCR units would pre-empt opportunities for reclaiming CCR 

from these CCR units for beneficial use of CCR. These commenters recommended that the final 
Document submitted to conclude E.O.12866 Review

413

rule create meaningful incentives for the beneficial use of CCR already in CCR units which will 

become unavailable to reclamation once a final cover system is put in place. For example, one 

commenter suggested that an incentive could be deferring deadlines for closure of a CCR unit if 

an owner or operator reduces its net tonnage by a set amount, such as 10,000 tons per year, if the 

CCR is beneficially used. EPA also received comments from several states that generally 

supported the rebuttable presumption concept. One state supported a longer rebuttable 

presumption time period of three years that could be extended if approved by the state on a caseby-case basis.

After consideration of all of the public comments, the Agency is adopting an approach 

that largely mirrors the approach outlined in the NODA. Closure of a CCR unit is triggered in 

one of three ways. The first is upon the known final receipt of waste (CCR or otherwise), or 

when an owner or operator removes the known final volume of CCR from the CCR unit for the 

purpose of beneficial use of CCR. Under these scenarios, the final rule requires an owner or 

operator to commence closure of the CCR unit within 30 days of such known final receipt or 

known final volume removal, whichever date is later.

The second way closure can be triggered relates to “idled” CCR units. This applies to 

situations in which the CCR unit has remaining disposal, treatment, or storage capacity, or there 

has been a temporary pause in the removal activities of CCR from the CCR unit. In these 

situations, the rule establishes a presumption that the owner or operator must initiate closure of 

the CCR unit no later than two years after the most recent receipt of CCR or any non-CCR 

wastestream, or no later than two years after the most recent date that CCR was removed from 

the CCR unit for the purpose of beneficial use, whichever date is later. The rule, however, 

provides procedures for an owner or operator of the CCR unit to rebut this presumption and 
Document submitted to conclude E.O.12866 Review

414

obtain additional time, provided the owner or operator can make the prescribed demonstrations.

The final way closure is triggered is when a CCR unit fails to meet certain of the 

technical criteria. Specifically, an owner or operator may be compelled to close a CCR unit in 

the following circumstances: (1) if the CCR unit has been sited inappropriately; i.e., cannot meet 

the applicable location criteria; (2) if an unlined CCR surface impoundment is found to 

contaminate groundwater in excess of a ground water protection standard; or (3) if a CCR 

surface impoundment cannot demonstrate the minimum factors of safety regarding structural 

integrity of the CCR unit. When closure is triggered under these circumstances, the owner or 

operator must initiate closure of the CCR unit within six months. Each of these is discussed in 

more detail below.

i. “Known Final Receipt” of CCR

Several commenters suggested that the rule not link the deadlines to initiate closure 

solely to when a CCR unit ceases to receive CCR. Many of these commenters provided 

information that CCR units also serve functions other than managing CCR, including the 

management of other wastes or water treatment. Thus, while there are periods of time that 

certain CCR units will receive both CCR and non-CCR wastes, there are also other times when 

the same CCR unit will only receive non-CCR wastes or perform other forms of active waste 

management in the unit, e.g., specific water treatment functions. EPA agrees that these are 

legitimate waste management activities, and EPA is aware of no risks that would warrant 

cessation of such activities simply because the unit is no longer receiving CCR. Therefore, in 

response to these comments, the final rule no longer requires closure based solely upon the 

receipt of CCR. Instead, the final rule requires closure to be initiated after the CCR unit ceases 

to receive any waste or wastestream into the CCR unit. See §257.102(e)(1) and (e)(2) in the rule.
Document submitted to conclude E.O.12866 Review

415

The Agency also agrees with those commenters that supported delaying the 

commencement of closure of a CCR unit if substantial quantities of CCR are removed from the 

CCR unit for the beneficial use of the waste. This could include, for example, removal of CCR 

from a CCR unit followed by its use as a partial replacement for Portland cement. As discussed 

in Unit IV.B of this preamble, EPA has identified significant benefits from reducing the disposal 

volumes of CCR in CCR landfills and CCR surface impoundments, including reduced risks 

associated with the practice of CCR disposal, benefits from reducing the need to mine and 

process virgin materials, and energy and greenhouse gas benefits. EPA finds these potential 

benefits compelling and is therefore revising the closure requirements in the rule to 

accommodate the removal and beneficial use of CCR. EPA has therefore revised the rule to 

provide that closure of an otherwise idled CCR unit is not immediately triggered, as long as the 

owner or operator is removing substantial quantities of CCR from the unit. However, once 

removal of CCR for beneficial use no longer taking place, the rule would require the owner or 

operator to initiate closure of the CCR unit. See §257.102(e)(1) and (e)(2) in the rule.

After considering comments received regarding the specific timeframe by which closure 

must be initiated following known final receipt of wastes, the Agency is finalizing the 30 day 

timeframe from the proposed rule. Several commenters expressed concern that 30 days is too 

short because it does not account for the potential that weather or seasonal concerns may 

interfere or cause substantial delay. The Agency acknowledges that weather or seasonal effects 

can delay certain activities, but disagrees that the rule provision needs to be revised to account 

for those. This provision does not require that specific actions or activities must be initiated 

during this 30-day period. For example, the rule does not require the installation of the final 

cover system (or the commencement of removal of CCR from the CCR unit) necessarily begin 
Document submitted to conclude E.O.12866 Review

416

within this 30-day period. Instead, the provision is more flexible; the owner or operator can 

initiate closure by taking other actions necessary to implement the closure plan that are not 

weather or seasonal dependent, such as turning off pumps supporting sluice lines or taking any 

steps necessary to comply with any state or other agency standards that are a prerequisite to 

initiating closure. Provided the owner or operator has started to take the measures to implement 

the closure plan that can be feasibly undertaken, the facility will have complied with this 

requirement.

The 30-day period remains equally appropriate under the wider provision that allows 

closure to be triggered either by the known final receipt of all wastes in the unit, or upon the 

known final volume removal of CCR for beneficial use of CCR. There are no facts unique to 

these circumstances that would necessitate an extension beyond the 30 days timeframe. 

Furthermore, as the terms “known final receipt” and “known final volume removal” suggest, the 

owner or operator has made the determination to cease managing waste in the CCR unit, or to 

cease removing CCR from the CCR unit for beneficial use purposes. This will likely occur in 

situations where the CCR unit is reaching its disposal capacity (or treatment capacity when the 

CCR unit is receiving non-CCR wastestreams) or the owner or operator intends to close the CCR 

unit for other purposes (e.g., the closing of a CCR surface impoundment following conversion to 

dry handling of CCR). Given that these situations can generally be anticipated and planned for 

in advance, EPA is not aware of circumstances that would prevent owners or operators from at 

least commencing closure within this 30-day period. In summary, the owner or operator must 

commence closure of the CCR unit with 30 days of known final receipt of CCR or any non-CCR 

wastestream, or within 30 days of known final removal of CCR for beneficial use, whichever 

date is later.
Document submitted to conclude E.O.12866 Review

417

ii. Temporarily Idled Units

This situation involves CCR units with remaining CCR disposal or storage capacity (or 

treatment capacity for non-CCR wastestreams) that may sit idle for extended periods of time 

(e.g., potentially years at a time); however, the owner or operator intends to continue to maintain 

the idled unit to receive CCR or non-CCR wastestreams in the future. EPA proposed that these 

CCR units could remain idle for up to one year, but that closure of the CCR unit would have to 

be initiated no later than one year after the most recent receipt of CCRs. See 75 FR 35252 

(proposed §257.100(j)). The majority of commenters claimed that one year was too short and 

would require the premature closure of CCR units that would be needed in the future. In 

response to these comments and new information documenting examples of legitimate 

circumstances in which CCR units were idled for more than one year, EPA solicited comment on 

a revised approach to establish longer timeframes to initiate closure for temporarily idled CCR 

units. As discussed previously, this approach entailed establishing a rebuttable presumption that 

if the CCR unit has not received waste within a specified period of time (i.e., 18 months to two 

years), the CCR unit would be considered inactive and closure of the CCR unit would be 

required. However, this time could be extended beyond the 18 months or two years if the facility 

could substantiate certain findings. See 78 FR at 46945.

After considering comments received, the Agency is essentially finalizing the approach 

presented in the NODA. Specifically, in situations where the CCR unit has remaining disposal 

or storage capacity (or treatment capacity for non-CCR wastestreams) and there is a reasonable 

likelihood that the CCR unit will receive additional CCR or non-CCR waste in the future, the 

final rule allows the owner or operator to keep the CCR unit available for use for up to two years. 

However, if the CCR unit has not received CCR or any non-CCR waste within two years of the 
Document submitted to conclude E.O.12866 Review

418

last receipt of CCR or any non-CCR waste, whichever date is later, the rule requires closure of 

the CCR unit unless the owner or operator can document that additional time is necessary to 

accommodate routine operations and legitimate waste management activities.

The Agency agrees that it is not necessary to require closure of temporarily idled CCR 

units after one year. Information in the record documents numerous examples of legitimate 

circumstances in which CCR units were idled for more than one year. In most of the examples 

provided CCR units are temporarily idled for periods that can last more than one year, but 

typically use of the CCR units resumes within approximately two years. Based on this 

information EPA has concluded that a two year timeframe before presumptively requiring 

closure of a CCR unit would be more consistent with current practice, and is better supported by 

the available information.

This same information documented that there can be situations in which a CCR unit is 

idled for longer periods of time (e.g., a coal-fired boiler may be idled for years during which 

another fossil fuel is burned (e.g., natural gas), and the CCR unit will be needed when the utility 

returns to coal burning. In order to obtain additional time beyond two years, the owner or 

operator must document in writing both that the CCR unit has remaining disposal or storage 

capacity and the facts that support a conclusion that there is a reasonable likelihood that the CCR 

unit will accept CCR or non-CCR waste in the foreseeable future. The facility would need to 

substantiate those findings, including the specific reasons the owner or operator believes “that 

there is a reasonable likelihood that CCRs will be disposed in the waste disposal unit.” These 

findings would need to be certified by the owner or operator of the CCR unit.

The rule identifies examples of specific scenarios that would support a determination that 

there is a continuing need for the unit to support future waste management activities (e.g., that 
Document submitted to conclude E.O.12866 Review

419

the CCR will resume receiving CCR or non-CCR waste in the future). These are intended to be 

illustrative rather than an exclusive list; there may well be additional circumstances in which 

routine operations or legitimate waste management practices would support the necessary 

determination. The particular situations identified in the rule generally match those discussed in 

the NODA or reflect situations identified in public comments. Specifically, the rule identifies 

four particular circumstances: (1) Normal plant operations include periods during which the 

CCR unit does not receive wastes (CCR or non-CCR wastestreams). This may include the 

alternating use between one CCR unit that receives CCR while dewatering or removing CCR 

from a second unit. (2) The CCR unit is dedicated to a coal-fired boiler unit that is temporarily 

idled (i.e., CCR is not being generated) and there is a reasonable likelihood that the coal-fired 

boiler will resume operations in the future. (3) The CCR unit is dedicated to an operating coalfired boiler (i.e., CCR is being generated); however, no CCR is being placed in the CCR unit 

because the CCR is being entirely diverted to beneficial uses, but there is a reasonable likelihood 

that the CCR unit will again be used in the foreseeable future. (4) The CCR unit currently 

receives only non-CCR wastestreams and those non-CCR wastestreams are not generated for an 

extended period of time, but there is a reasonable likelihood that the CCR unit will again receive 

non-CCR wastestreams in the future. As noted, a facility must substantiate these findings; it is 

not sufficient to merely repeat the words of the regulation and conclude that additional time is 

warranted.

The final rule allows an owner or operator to obtain additional two-year time extensions 

for as long as the owner or operator continues to be able to provide a factual basis to justify the 

need for additional time via a written demonstration. Because these idled units must continue to 

comply with all applicable technical requirements, including those for groundwater monitoring, 
Document submitted to conclude E.O.12866 Review

420

corrective action, and structural stability, a fixed or definitive limit on the amount of time that a 

CCR unit can sit idle is not necessary.

In addition, the Agency agrees that the final rule should better define the actions or 

activities that constitute “initiation of closure” of a CCR unit. A clear definition will assist in the 

implementation and understanding of the rule. Commenters suggested a number of actions or 

activities, any one of which would be sufficient to show that closure of the CCR unit has been 

initiated. Examples provided by the commenters included the removal of CCR slice lines; 

beginning the necessary permitting processes (i.e., submitting a completed permit application); 

turning off pumps supporting the sluice lines; preparing a bid for contractors; or procuring 

capping materials such as clay or top soil.

The final rule specifies that closure has been initiated when the owner or operator 

takes two actions. The first action is that the owner or operator must have permanently ceased 

placing CCR and non-CCR wastestreams in the CCR unit. As suggested by commenters, 

permanent removal of CCR sluice lines or inactivation of the pumping system supporting the 

sluicing operation would be evidence that placement of CCR and non-CCR wastestreams has 

ceased. The second action is that the owner or operator must have taken steps to implement the 

written closure plan required by the rule. This second action would include submitting a 

completed application for any required state or agency permit or permit modification in order to 

implement closure of the CCR unit, or taking any steps necessary to comply with any state or 

other agency standards or regulations that are a prerequisite to initiating or completing the 

closure of the CCR unit. Once the owner or operator has completed both of these actions, 

closure of the CCR unit has been initiated for purposes of this rule. See §257.102(e)(3) in this 

rule.
Document submitted to conclude E.O.12866 Review

421

iii. Closure for Cause

Finally, the Agency is clarifying that the closure initiation timeframes specified 

above – the 30 day period for known final receipt or known final volume removal and the 2 year 

period for temporarily idled CCR units – do not apply to closures initiated for cause. As 

discussed elsewhere in the preamble, the final rule requires certain CCR surface impoundments 

and CCR landfills to close. The situations include: unlined CCR surface impoundments whose 

groundwater monitoring shows an exceedance of a groundwater protection standard; existing 

CCR surface impoundments that do not comply with the location criteria; CCR surface 

impoundments that are not designed and operated to achieve minimum safety factors; and 

existing CCR landfills that do not comply with the location criteria for unstable areas. In these 

situations, the final rule specifies that the owner or operator must initiate closure activities within 

six months of making the relevant determination that the CCR unit must close.

b. Deadlines to Complete Closure

In response to the August 2013 NODA, many utility commenters stated that the time 

period to complete closure must be sufficiently flexible to account for the inherent uncertainties 

in predicting a closure schedule. These commenters point to potentially innumerable 

complications and circumstances beyond the control of the owner or operator that render it 

nearly impossible to predict with precision when the closure of a CCR unit will be completed. 

These commenters also believe it is impractical and unrealistic for the rule to subject the closure 

of CCR units to any type of fixed regulatory structure. They maintained their position from the 

proposed rule that it would be impossible to properly complete closure of most CCR surface 

impoundments within 180 days. Their recommendation is to allow closure timeframes to be 

governed by the a state-approved closure process, which would include the owner or operator 
Document submitted to conclude E.O.12866 Review

422

developing and submitting a closure plan to the state and mechanisms for the state to verify and 

enforce compliance with all closure requirements, including the closure plan. Under this 

approach, the owner or operator’s compliance with the requirements of the state-approved 

closure process (including following the closure plan, completing mitigation, etc.) would 

represent compliance with this rule’s closure requirements. For CCR units not subject to a stateapproved closure process, these commenters recommended that the owner or operator should 

demonstrate compliance with the CCR closure requirements by submitting a closure plan to the 

state that is certified by an independent professional engineer. In this case, because there is not 

direct state oversight and administration of the closure process, the timelines in the closure plan 

could be subject to a modified set of tiered timeframes for completing closure, provided owner or 

operators could demonstrate that more time is needed to close the unit on a case-by-case basis.121 

These commenters also opposed any closure approach with firm and inflexible timeframes 

because no single factor (e.g., the acreage of the CCR unit or the volume of CCR in the unit) is 

determinative in all instances of how long it will take to complete closure of the CCR unit. 

Commenters also cautioned that pre-closure closure plans (and the closure schedules contained 

therein) may not be an actual reflection of the time it will take to close the unit due to unforeseen 

or variable conditions. Finally, these commenters also generally opposed the idea discussed in 

the NODA of petitioning the Agency for a site-specific rule to vary from a generally applicable 

deadline.

 

121

 The tiered timeframes for completing closure could be based on the size of the CCR unit (after obtaining 

necessary state and local approvals): (1) Within 3 years for an impoundment with an area less than 20 acres; (2) 

Within 5 years for an impoundment between 20 and 50 acres; (3) Within 8 years for an impoundment between 50 

and 75 acres; (4) Within 10 years for an impoundment with an area of 75 acres or more; and (5) Within 180 days for 

a landfill. Under this approach, the owner or operator could demonstrate the need for additional time to close the 

CCR unit.
Document submitted to conclude E.O.12866 Review

423

Many commenters described the many factors that could affect timeframes for closure of 

a CCR unit. Most comments were specific to CCR surface impoundments whose closures are 

typically more complex as compared to CCR landfills due to the presence of water in 

impoundments. Factors most often cited by the commenters that may affect the time required to 

close a CCR unit included: the size and volume of CCR in the unit; the geotechnical 

characteristics the CCR; the type or design of the surface impoundment (i.e., diked, incised, 

valley fill, and side hill); the need to coordinate or obtain approvals from state permitting 

officials; the availability of qualified engineers, contractors, and materials since closing a CCR 

unit is a specialized activity, especially given that many units may be required to close 

simultaneously; climate and weather that can affect dewatering operations and the length of a 

construction season; the time needed to obtain replacement disposal capacity for a closing unit 

that would ensure ongoing facility operations; and dam safety considerations during closure. 

Many of commenters identified that the dewatering process (an early necessary step in the 

closure process) as being a site-specific issue, as the time that will be needed to dewater an 

impoundment can vary considerably depending on the type of CCR unit, the volume of CCR in 

unit, and the geotechnical properties of the CCR. Several commenters also cited that closure 

times for some CCR units will require substantial volumes of fill material to properly grade a 

closing surface impoundment to facilitate positive drainage from the closed unit. These 

commenters provided estimates on the volumes of fill material needed and showed that the 

earthmoving aspect of this step alone can take many years in some cases.

Several state commenters generally supported the tiered closure alternative discussed in 

the NODA. However, these commenters urged EPA to include provisions in the rule to provide 

flexibility for closing units to demonstrate the need for additional time on a case-by-case basis.
Document submitted to conclude E.O.12866 Review

424

i. Timeframes for Completing Closure

In the August 2013 NODA the Agency solicited comment on ways to establish categories 

of timeframes that would adequately account for the various factors that can affect the amount of 

time need to properly close a CCR surface impoundment. One approach discussed in the NODA 

was called the “tiered approach” that was based on comments received in response to the 

proposed rule. Under that approach, the final rule would establish fixed timeframes to complete 

closure that varied depending on the size of the impoundment (i.e., surface area acreage). The 

Agency stated in the NODA that the concept of a tiered approach was appealing; however, the 

precise basis for the distinctions (i.e., unit size cutoffs) and timeframes were not clear. EPA 

further explained its concern that factors other than size (e.g., climate, geography, unit 

configuration) would also appear to be relevant, and that any timeframes should account for 

those other factors. EPA encouraged commenters interested in supporting a tiered approach to 

provide the rationale and data to support any suggested categories of timeframes. 78 FR 46946. 

Most commenters opposed the tiered approach by itself (i.e., an approach without an 

accompanying process by which an owner or operator could obtain additional time due to sitespecific circumstances) because they felt there simply are too many factors that can affect 

closure timeframes. These commenters concluded that basing closure timeframes on a subset of 

factors would not be appropriate. As one commenter noted, a 20 acre impoundment 10 feet deep 

can likely be dewatered and closed more quickly than a 20 acre impoundment 30 feet deep.

After considering comments and information available on closure timeframes, EPA has 

concluded that there are insufficient data and information to adopt the kind of tiered approach 

discussed in the NODA. EPA is convinced that the available information does not support an 

approach that would establish fixed and definitive timeframes for closure, based on a select 
Document submitted to conclude E.O.12866 Review

425

subset of factors that distinguish between surface impoundments (e.g., a 50 acre diked 

impoundment holding 500 acre-feet of CCR with a hydraulic conductivity of 1 x 10-5centimeters 

per second located in a state in the southwest with a permitting program would be required to 

close in 4 1⁄2 years, while a 50 acre cross valley impoundment holding 1,500 acre-feet of CCR 

with a hydraulic conductivity of 1 x 10-6centimeters per second located in a state in the upper 

midwest with a permitting program would be required to close in 7 years, etc). While 

information is available for surface impoundments on certain factors, such as the size and type of 

the unit and geographic information, the Agency has little to no data for a number of other key 

factors. For example, EPA has no information on the geotechnical properties of the CCR that 

can affect the time needed to dewater a unit, the volumes of clays, soils, and other materials that 

will be needed for closure, and information on the time needed to obtain state approvals (in 

accordance with state CCR programs) related to closure of a unit.

In discussing the tiered approach EPA noted that commenters to the proposed rule had 

suggested that the largest CCR surface impoundments (i.e., those having a surface area greater 

than 75 acres) should be subject to a site-specific deadline to complete closure. In the NODA the 

Agency explained that a site-specific deadline may not be practicable unless the rule were to 

establish a “variance” process as part of the rule. 78 FR 46946. Under a variance approach, 

EPA would establish a specific deadline (e.g., closure must be completed no later than five years 

from the date closure activities are initiated), but would allow facilities to petition EPA for a sitespecific rule to establish an alternate deadline. In response to the NODA, some commenters 

expressed interest in such an approach, but other commenters found the approach not practicable 

since each owner or operator would need to petition the Agency for a site-specific rule. Some 

commenters believed that a site-specific rule process, which would necessarily involve a notice 
Document submitted to conclude E.O.12866 Review

426

and comment process, would be an unwieldy process leading to unnecessary delays. The 

Agency agrees that this is also not a practical alternative to establish timeframes to complete 

closure.

Recognizing the numerous factors that can affect the amount of time needed to close an 

impoundment, many commenters suggested EPA not establish any type of fixed regulatory 

deadline for closure. Instead, these commenters recommended that the rule allow closure 

timeframes to be governed by a state-approved closure process. Under this process suggested by 

commenters, and adequate state-approved closure process would include one where the owner or 

operator developing and submitting a closure plan to the state and mechanisms for the state to 

verify and enforce compliance with all closure requirements, including the closure plan. Under 

the commenter’s recommendation, compliance with the requirements of the state-approved 

closure process would not be compliance with the closure requirements of this rule. As 

discussed elsewhere in this preamble, under subtitle D of RCRA, the Agency cannot rely on the 

existence of a state permitting authority to implement the subtitle D requirements.

Some other commenters suggested EPA not establish any type of fixed regulatory 

deadline for closure in the rule, and instead rely on the closure plan developed and certified by a 

professional engineer. The Agency disagrees that this approach would meet the protectiveness 

standard of RCRA section 4004(a). CCR units present significant risks, and it is critical that 

facilities complete closure expeditiously – particularly those that are closing because they are 

structurally unsound or are contaminating groundwater. To be able to determine that the rule 

will be protective, the final rule must limit the discretion of individual facilities, many of whom 

may have significant incentives for delay, and avoid the potential for abuse. Moreover, in 

contrast to corrective action, where EPA was truly unable to establish an outer limit on the 
Document submitted to conclude E.O.12866 Review

427

necessary timeframes – including even a presumptive outer bound – closures, while complex, do 

not vary to the same degree as site remediation actions. Consequently, as discussed later in this 

section, the available data were sufficient to support the establishment of definitive timeframes. 

Most commenters, however, were generally supportive of an approach that would 

establish timeframes for closure, whether in a tiered-like approach (i.e., timeframes for closure 

based on one or more characteristics of the unit) or under a “rebuttable presumption” approach, 

so long as the rule would provide the owner or operator a process or procedures to demonstrate 

the need for additional time. As explained in the NODA, such an approach could be 

implemented by establishing a presumption that facilities complete closure within a specified 

timeframe, such as five years, unless the facility could document that closure is not feasible to 

complete within the presumptive timeframe.

After consideration of all of the public comments, EPA is adopting an approach that takes 

elements from two of the alternatives discussed in the NODA: the concept of tiered timeframes 

based primarily on the size of the surface impoundment, and the concept of a rebuttable 

presumption. The final rule establishes a presumption that the owner or operator must complete 

the closure of a CCR surface impoundment within five years of initiating closure activities. For 

CCR landfills the presumption is that the owner or operator must complete closure within six 

months of initiating closure activities. The rule, however, provides procedures for an owner or 

operator to rebut either presumption and obtain additional time, provided the owner or operator 

can make the prescribed demonstrations. For CCR surface impoundments, the amount of 

additional time beyond the five years varies based on the size (using surface area acreage of the 

CCR unit as the surrogate of size) of the unit. For impoundments 40 acres or smaller, the 

maximum time extension is two years. For impoundments greater than 40 acres, the maximum 
Document submitted to conclude E.O.12866 Review

428

time extension is five two-year extensions (ten years) and the owner or operator must 

substantiate the factual circumstances demonstrating the need for each two-year extension. For a 

CCR landfill, the amount of additional time beyond the six months does not vary according to 

the size of the landfill, rather the maximum time extension is two one-year extensions (two 

years) for any CCR landfill. The owner or operator must substantiate the factual circumstances 

demonstrating the need for each one-year extension.

ii. CCR Surface Impoundment Timeframes

To develop these timeframes the Agency began by identifying the period of time in 

which most surface impoundments could feasibly complete closure. EPA intended this period of 

time to serve as the basis for the rebuttable presumption of the rule. As EPA recognized in the 

NODA, a timeframe that would be feasible for the largest units would grant more time than 

could be justified to complete the closure of smaller units. The closure of CCR units, and 

particularly the closure of CCR units that are compelled to close because they fail to comply with 

the rule’s requirements (e.g., are structurally unstable or are contaminating groundwater), needs 

to occur as expeditiously as is feasible. While these units (and particularly the larger CCR 

surface impoundments) are in the process of closing, they continue to present risks to human

health and the environment. On the other hand a presumptive time period that is feasible for a 

small percentage of units would simply result in a greater number of facilities that would need to 

obtain time extensions. It is well established that the law cannot compel actions that are 

physically impossible, “lex non cogit ad impossibilia”, and it is incumbent on EPA to develop a 

regulation that does not in essence establish such a standard. 

The available information shows that CCR surface impoundments vary in size by an 

order of magnitude (i.e., from less than one acre to nearly 1,000 acres). EPA evaluated the 
Document submitted to conclude E.O.12866 Review

429

information on the size distribution of CCR surface impoundments in its database of survey 

results from EPA’s 2009 Information Request.122 Through this effort, EPA received a 

substantial amount of factual information from 240 utility facilities covering 676 surface 

impoundments, including surface area information on over 650 impoundments. The database of 

survey responses shows that the median surface impoundment is approximately 14 acres in size, 

75 percent of impoundments are 50 acres or smaller, 80 percent of impoundments are 66 acres or 

smaller, and 90 percent of impoundments are 111 acres or smaller.

Available information on actual and projected timeframes needed to close CCR surface 

impoundments of varying sizes (using surface area as the surrogate for size) is summarized 

below. Much of this information came from public comments from utilities. The largest CCR 

surface impoundment in this data set that has actually completed closure is a 40-acre unit that 

closed over a period of approximately five years (i.e., the surface impoundment at PPL 

Corporation’s Martins Creek Power Plant).123 This facility closed with waste in place, and 

included installation of a final cover system. According to the facility, this CCR unit ceased 

receiving wastewater in January 2008, and the closure work began with dewatering the unit and 

preparing the revised closure plan and permit modification applications. Installation of the final 

cover, in addition to final soil grading and seeding of the unit was completed in spring 2012. By 

early 2013, all remaining closure actions were completed and state regulators issued final 

approvals in July 2013. EPA gave substantial weight to this information because (1) this was a 

CCR surface impoundment—the units of greatest relevance to the issue at hand; (2) the closure 

 

122

 More information on EPA’s Information Request, including a data base of survey responses, can be accessed at 

http://www.epa.gov/epawaste/nonhaz/industrial/special/fossil/surveys/index.htm.

123

 EPA included information on the planned closure of this CCR surface impoundment in the NODA. 78 FR 

46945. The closure plan estimated that the closure process would take approximately three years to complete.
Document submitted to conclude E.O.12866 Review

430

was completed recently, and so would accurately reflect current and available engineering 

practices; and (3) the facility actually unit actually completed closure of the unit. See EPA-HQRCRA-2012-0028-0103 and EPA-HQ-RCRA-2012-0028-0113.

As another example, American Electric Power provided some information on the recent 

closure of a CCR surface impoundment in 2013. This 21-acre unit had been inactive for several 

years and was closed over two construction seasons. The impoundment was closed by leaving 

CCR in place and installing a composite cap, in addition to the installation of hydraulic 

appurtenances to control the design storm events. See EPA-HQ-RCRA-2012-0028-0067.

Cleco Corporation provided planned closure timeframes contained in existing permits for 

its CCR surface impoundments. For three of its CCR surface impoundments, which in aggregate 

totaled 66 acres, Cleco Corporation estimated that it could take approximately one year to 

complete closure, which would be accomplished by leaving CCR in place and installing a final 

cover system. Cleco Corporation also estimated that it would take approximately nine months to 

complete closure of two additional CCR surface impoundments, with an aggregate acreage of 5.5 

acres, by removing CCR from the CCR units, (i.e., clean closure of the units). Information on 

the size of any of the five CCR units was not provided, which complicates the Agency’s ability 

to assess the closure of any of the individual CCR units. In addition, the time period appears to 

begin when dewatering operations are initiated and the comments do not discuss how much time 

may be needed to obtain any necessary approvals from the state prior to commencing closure 

activities. See EPA-HQ-RCRA-2012-0028-0106.

Similarly, Xcel Energy stated in its comments to the NODA that it closed four CCR 

surface impoundments at its Northern States Power of Minnesota’s Minnesota Valley Plant by 

removing all of their contents. See EPA-HQ-RCRA-2012-0028-0079. While the commenter did 
Document submitted to conclude E.O.12866 Review

431

not provide any information on the time needed to close the four CCR units, other information 

available to the Agency indicates that closure took place sometime after May 2009 and was 

completed prior to September 2013. Based on information learned from Xcel Energy in 

response to EPA’s request for information from May 2009, the four CCR units at the Minnesota 

Valley Plant each have a surface area less than one acre. In addition, the response to the 

information request showed that one CCR surface impoundment was nearly full of ash, a second 

was more than half full, and the final two CCR units were less than one quarter full.

In the August 2013 NODA, the Agency solicited comment on a draft plan to close two 

CCR surface impoundments at Santee Cooper’s Grainger Generating Station in South Carolina. 

78 FR 46945. The plan estimated that closure of the two CCR units, approximately 42 and 39 

acres in surface area, could be accomplished during a three year period. This original estimate 

was based on closing the unit with waste in place and installing a final cover. However, Santee 

Cooper has since amended its draft plan and is now pursuing closure by removal of CCR and 

transport off-site for either disposal or beneficial use.124 The revised draft envisions the 

complete removal of CCR from both CCR units and also one foot of underlying soil beneath the 

units. In total, the draft closure plan estimates that approximately 1.3 million cubic yards of 

CCR and underlying soil will be removed from both units – approximately 900,000 cubic yards 

from one unit and 400,000 cubic yards from the second – over a period of six to ten years.

The Florida Electric Power Coordinating Group (FCG) claimed that, based on FGC 

member experience, closing a 30 acre CCR surface impoundment is expected to take 

 

124

 “Amended Closure Plan Wastewater Ash Ponds, Grainger Generating Station, Conway, South Carolina,” 

January 2014.
Document submitted to conclude E.O.12866 Review

432

approximately two years to complete, but provided no additional information or details. See 

EPA-HQ-RCRA-2012-0028-0064.

The Utility Solid Waste Activities Group (USWAG) provided another projected closure 

schedule for a 20 acre CCR surface impoundment operated by Luminant. This facility was in the 

process of closing the unit when the comments were prepared. The schedule estimated that 

completion of all closure activities, would take approximately 45 months (3 years, 9 months) to 

complete. However, the commenter also states that, when complete, the “full closure period will 

take approximately 84 months (7 years) due to the unique circumstances of that closure.” No 

other information was provided on this closure to explain the “unique circumstances” that 

warrant such an extended period of time. See EPA-HQ-RCRA-2012-0028-0113.

There is other information in these data that indicates that larger impoundments may be 

able to complete closure within approximately the same timeframes as smaller units. For 

example, the data included the projected closure of a 100-acre CCR surface impoundment over a 

4 1⁄2 year period, which seems to indicate that larger units may be able to close in approximately 

the same period of time. However, the Agency gave substantially less weight to this 

information for a number of reasons. Most critically, this information merely demonstrated 

projected timeframes for CCR surface impoundments, not actual timeframes that had been 

achieved. In addition, for some of these data, it was unclear whether the circumstances that 

allowed for completion within this timeframe were generally applicable to the majority of CCR 

surface impoundments. In one instance, the commenter noted that the time to complete closure 

was shorter than would normally be expected because the impoundment was being closed well 

before it reached full capacity and because water in the impoundment could be pumped into an 

adjacent impoundment. The commenter also noted that the impoundment had been built with a 
Document submitted to conclude E.O.12866 Review

433

leachate collection system to facilitate dewatering at closure. See EPA-HQ-RCRA-2012-0028-

0113.

Moreover, the majority of commenters claimed that it would take substantially longer 

than five years to close the largest impoundments. For example, USWAG stated that one of its 

members obtained “approval for a closure plan for a 343-acre surface impoundment that 

provided for a twelve-year closure period to ensure adequate time to complete dewatering of the 

impoundment, assure the stability of the dewatered CCRs, and uniformly construct the slope of 

the final cover materials.” No other information was provided on this closure example. See 

EPA-HQ-RCRA-2009-0640-10483. USWAG also provided information on the closure of the 

CCR surface impoundment at First Energy’s Little Blue Run Disposal Area. This 950 acre 

surface impoundment, which is the largest CCR surface impoundment in the country, has a 

projected closure period of 15 years.

Similarly, to illustrate the time required simply for earthmoving operations to close a 

large CCR surface impoundment (in their example, 350 acres), Duke Energy Corporation 

estimated that the time needed in the schedule to deliver and place the necessary volume of 

materials for construction of the final cover and the sub-base to the cover system could take 

between nine and 12 years. This estimate is based on the need for approximately 10 to 11 

million cubic yards of fill to construct and shape the sub-base of the final cover and the cover 

system itself that would require nearly 500,000 truckloads to deliver. See EPA-HQ-RCRA2012-0028-0095.125

 

125 EPA also received information from Consumers Energy Company on the closure of three former fly 

ash surface impoundments at the JR Whiting plant. These surface impoundments (combined) totaled 

approximately 52 acres and are scheduled to be closed with a final cover over an approximately 12-year 
Document submitted to conclude E.O.12866 Review

434

Collectively, this information formed the basis for the 5 year presumptive default. 

As noted the median size of CCR surface impoundments is approximately 14 acres, and 75 

percent of impoundments are 50 acres or smaller. The information presented by the utilities 

documents that impoundments as large as 66 acres under normal circumstances can close within 

2-3 years. EPA therefore expects that most, if not all, units should be able to complete closure 

within 5 years. For all but the very largest units, this timeframe would even accommodate 

potential delays caused by weather or any other unpredictable variables. This is clearly 

demonstrated by the examples presented by public comments, and by the recent example of the 

40-acre CCR surface impoundment in Martins Creek that closed within 5 years.

EPA also notes that 5 years is the timeframe Congress mandated for the completion of 

open dumps to close or upgrade. While the closure times apply generally to all units—both 

those whose closure is mandated by this final rule and those that close because the facility 

decides to do so—the statutory directive provides further support for EPA’s decision. 

But as many commenters stated, initial estimates can and often do vary from actual 

closure times due to unforeseen or variable conditions. EPA acknowledges that a host of 

variables can, and frequently do, delay closure activities, such that the initial time estimates to 

complete closure of the unit are ultimately exceeded. For example, the 40 acre impoundment at 

Martins Creek Power Plant discussed above was initially scheduled in its closure plan to be 

 

period. The commenter claimed that the extended time for closure “was necessary to allow dewatering 

and the filling of numerous voids, but principally to allow the generation of fly ash to allow the placement 

of structurally placed, low permeability ash to provide minimal required slopes for closure and to serve as 

the select layer for the flexible membrane liner.” See EPA-HQ-RCRA-2012-0028-0068. Information on 

the individual size of any of the three CCR units was not provided in the comments, which complicates 

any assessment of the time needed to complete closure of any single CCR unit. Because the facility 

appears to be continuing to use the unit to actively manage waste, EPA does not consider this to be 

representative of a typical closure process.
Document submitted to conclude E.O.12866 Review

435

completed within three years; however, closure ultimately took five years to complete. The 

additional two years was due to the need to obtain approval of a modified closure plan from the 

state, as well as modifications to three permits, in addition to the need to obtain other local 

planning approvals. Further time was also needed to accommodate the public notice and 

comment processes for several of the permits and approvals.

EPA also recognizes that a number of unpredictable or variable conditions that can affect 

the time needed to close a CCR unit are not within the control of the owner or operator. For 

example, some states require review and approval of a closure plan prior to initiating of closure 

activities. See, for example, 25 Pa. Code §§ 288.292(b) and 289.311(b) for CCR landfills and 

CCR surface impoundments, respectively. Another commenter noted that in Illinois, permits 

from several different authorities may need to be obtained to commence closure, including the 

Illinois Department of Natural Resources, the U.S. Army Corps of Engineers, and the U.S. Fish 

and Wildlife Services.

Climate and weather can also impact the time needed to complete closure. For example, 

an unusually wet or short construction season can result in schedule delays; one commenter 

noted that in certain regions of the Midwest, it is possible for as much as 40 inches of rain to fall 

in a given season. 

To account for these complexities, a substantial majority of commenters requested that 

the final rule include the potential for time extensions, and several specifically referenced the 

need for a “force majeure” provision. One commenter also recommended that a “force majeure” 

clause should specifically include delays caused by court order (i.e., appeals of permits issued by 

state agencies causing judgments in court). Another commenter provided an example of a “force 

majeure” provision that could serve as a model: 
Document submitted to conclude E.O.12866 Review

436

An extension shall be granted for any scheduled activity delayed by an event of 

force majeure which shall mean any event arising from causes beyond the control of the 

owner that causes a delay in or prevents the performance of any of the conditions under 

this rule including but not limited to: acts of God, fire, war, insurrection, civil 

disturbance, explosion; adverse weather conditions that could not be reasonably 

anticipated causing unusual delay in transportation and/or field work activities; restraint 

by court order or order of public authority; inability to obtain, after exercise of reasonable 

diligence and timely submittal of all applicable applications, any necessary 

authorizations, approvals, permits, or licenses due to action or inaction of any 

governmental agency or authority; and delays caused by compliance with applicable 

statutes or regulations governing contracting, procurement or acquisition procedures, 

despite the exercise of reasonable diligence by representatives of the owner.

Events which are not force majeure include by example, but are not limited to, 

unanticipated or increased costs of performance, changed economic circumstances, 

normal precipitation events, or failure by the owner to exercise due diligence in obtaining 

governmental permits or performing any other requirement of this rule or any procedure 

necessary to provide performance pursuant to the provisions of this rule. 

EPA agrees that the rule should include procedures to obtain extensions of time to 

complete closure of the unit, based on the complexity of the activity. As previously noted, the 

law, including a regulation, cannot compel the impossible. However, because the record 

demonstrates that most units, even the larger units, can close within that 5 year timeframe, the 

final rule establishes a high threshold to obtain additional time. To account for those instances of 

true physical impossibility, the final rule limits extension to circumstances in which the owner or 
Document submitted to conclude E.O.12866 Review

437

operator can demonstrate that the additional time is needed due to factors that are truly beyond 

the facility’s control—i.e., could fairly be characterized as an example of “force majeure.” To 

obtain additional time, the owner or operator of the CCR unit must document in writing that 

identifies the exact reasons why additional time is needed. The regulation specifies that such 

reasons could include: (1) Complications stemming from the climate and weather, such as 

unusual amounts of precipitation or a significantly shortened construction season; (2) Time 

required to dewater a surface impoundment due to the volume of CCR contained in the CCR unit 

or the geotechnical characteristics of the CCR in the unit; (3) The geology and terrain 

surrounding the CCR unit will affect the amount of material needed to close the CCR unit; or (4) 

Time required or delays caused by the need to obtain State permits and/or to comply with other 

State requirements. These findings would need to be certified by the owner or operator of the 

unit, as well as by a qualified professional engineer.

The final rule limits the amount of time that closure can be extended based on the size of 

the CCR unit. Specifically, the rule allows CCR surface impoundments 40 acres or smaller a 

time extension of up to two years, while CCR surface impoundments larger than 40 acres can 

obtain up to five two-year extensions. The 40 acre size demarcation is based on the available 

information showing that surface impoundments of 40 acres or smaller routinely have either 

completed closure or are projected to be able to complete closure within timeframe shorter than 

five years. EPA expects that facilities will account for all potential delays that can reasonably be 

foreseen in planning their closure activities, and that this is feasible within this five year 

timeframe. Consequently the final rule restricts facilities with units of this size to a single 

extension to account for truly exception circumstances (e.g., Acts of God).
Document submitted to conclude E.O.12866 Review

438

The Agency also recognizes that there is more uncertainty for CCR surface 

impoundments larger than 40 acres. First, while available information documents that some 

CCR surface impoundments can be closed within this same five year period, the Agency is also 

has other information indicating that closure of units larger than 40 acres are expected to take 

much longer than five years. The largest surface impoundment in the country is approximately 

950 acres which is scheduled to cease receiving CCR by December 31, 2016 and commence 

closure in 2017. The facility’s projected closure period is 15 years for this unit. However, EPA 

currently has no data (anecdotal or otherwise) on the actual timeframes in which a surface 

impoundment of that size that has completed closure. Given that closure for the largest of 

surface impoundments could reasonably be expected to take more than five years to complete, 

the Agency has concluded that surface impoundments larger than 40 acres need to be provided 

with the possibility of additional time extensions beyond the two years provided to 

impoundments less than 40 acres. Based on available information, in particular the current 

estimates of the time needed to close the largest unit in the country, the rule authorizes a facility 

to obtain a maximum of five time extensions, totaling as much as ten years in two year 

increments to close a CCR surface impoundment greater than 40 acres. However, the owner or 

operator must substantiate the factual circumstances demonstrating the need for each two-year 

extension.

Several commenters also urged EPA to specify in the final rule what EPA intended by the 

phrase “completion of closure;” that is, that EPA define the activities or actions the owner or 

operator must complete to satisfy the closure requirements. For purposes of this rule, closure of 

a CCR unit is completed when the unit meets all of the requirements of this rule and the owner or 

operator obtains certification from a qualified professional engineer verifying that closure has 
Document submitted to conclude E.O.12866 Review

439

indeed been completed, consistent with all of the performance standard in the rule. While EPA 

recognizes that under some state programs closure is not considered complete until the owner or 

operator receives certification from the state, this is not a prerequisite to completion of closure 

under these federal rules.

iii. Closure Timeframes for CCR Landfills

Similar to the approach for CCR surface impoundments, EPA recognizes that there can 

be unforeseen and extraordinary circumstances that warrant additional time to close a CCR 

landfill. Accordingly, the rule adopts procedures analogous to those for CCR surface 

impoundments that allow the owner or operator to obtain additional time to complete the closure 

of a CCR landfill, provided the owner or operator can make the prescribed demonstrations. 

However, the amount of additional time the facility can obtain beyond the presumptive six 

month timeframe does not depend on the size of the landfill; rather the maximum time extension 

is two one-year extensions (two years) for any CCR landfill. As with the procedures for CCR 

surface impoundments, the owner or operator must substantiate the factual circumstances 

demonstrating the need for each one-year extension.

EPA developed this timeframe based on its review of the available information in the 

record regarding the timeframes for completing the closure of CCR landfills, some of which is 

summarized below. Additional information may also be found in the comment response 

document.

In response to the August 2013 NODA, Nebraska Public Power District (NPPD) 

provided information documenting that it completed closure of a 10 acre CCR landfill within 180 

days after the final volume of fly ash and bottom ash was placed in the CCR landfill. Closure 

was accomplished by leaving CCR in place and installing a final cover system. NPPD’s 
Document submitted to conclude E.O.12866 Review

440

comments do not indicate what year closure of this CCR landfill was completed. See EPA-HQRCRA-2012-0028-0076.

The Florida Electric Power Coordinating Group (FCG) stated in its comments that 

FGC member experience with CCR landfill closure has “demonstrated the need for a period of 

time greater than 180 days to complete closure activities.” However, the commenter did not 

provide any information indicating how long such closures actually took, nor any information to 

substantiate their claim. See EPA-HQ-RCRA-2012-0028-0064.

Overall, the closure of CCR landfills is less complex than the closure of CCR surface 

impoundments. Portions of the CCR landfills that reach final grade can be closed as other ares 

of the CCR landfill continue to receive CCR, which is typically not possible at CCR surface 

impoundments. Nor does the owner or operator need to dewater the unit, which appears to be 

the aspect of closure most likely to be a source of unanticipated circumstances. Finally, there is 

substantially less uncertainty with respect to the timeframes to complete the closure of CCR 

landfills, which are not all that different (in this respect) than landfills containing other forms of 

solid or hazardous waste. EPA therefore has greater confidence that a fixed period of two years 

will be adequate to account for the vast majority of circumstances.

c. Alternative Closure Requirements

The Agency is finalizing alternative closure requirements in two narrow 

circumstances for a CCR landfill or CCR surface impoundment that would otherwise have to 

cease receiving CCR and close, consistent with the requirements of §257.101(a), (b)(1), or (d). 

The first is where the owner or operator can certify that CCR must continue to be managed in 

that CCR unit due to the absence of both on-site and off-site alternative disposal capacity. 

§257.103(a). The second is where the owner or operator of a facility certifies that the facility will 
Document submitted to conclude E.O.12866 Review

441

cease operation of the coal-fired boilers no later than the dates specified in the rule, but lacks 

alternative disposal capacity in the interim. §257.103(b). Under either of these alternatives, 

CCR units may continue to receive CCR under the specified conditions explained below. In 

addition, under either alternative, the owner or operator must continue to comply with all other 

requirements of the rule, including the requirement to conduct any necessary corrective action.

1. No alternative CCR disposal capacity (§257.103(a)).

The Agency recognizes that the circumstance may arise where a facility’s only disposal 

capacity, both on-site and off-site, is in a CCR unit that has triggered the closure requirements in 

§257.101(a), (b)(1), or (d). As a result, the facility may be faced with either violating the closure 

requirements in §257.101 by continuing to place CCR in a unit that is required to close, or 

having to cease generating power at that facility because there is no place in which to dispose of 

the resulting waste. For example, while it is possible to transport dry ash off-site to alternate 

disposal facility that simply is not feasible for wet-generated CCR. Nor can facilities 

immediately convert to dry handling systems. As noted previously, the law cannot compel 

actions that are physically impossible, and it is incumbent on EPA to develop a regulation that 

does not in essence establish such a standard. 

Should a facility choose to comply with the regulation and stop generating power, there 

would be significant risks to human health that would arise if a community would be left without 

power for an extended period of time. As information in the record demonstrates, obtaining 

alternative capacity can sometimes require a substantial amount of time (e.g., if the facility needs 

to construct alternative capacity, including potentially the need to locate an alternative site or 

purchase additional property). EPA recognizes that there are also significant risks to human 

health and the environment, as demonstrated throughout this preamble, from a leaking or 
Document submitted to conclude E.O.12866 Review

442

improperly sited CCR unit, and that these risks justify requiring those units to either retrofit to 

meet the federal criteria established in the final rule or close. EPA also acknowledges that in the 

interim period while the owner or operate seeks to obtain additional capacity, the risks associated 

with the continued use of these units will be significant. However, the agency believes that the 

risks to the wider community from the disruption of power over the short-term outweigh the 

risks associated with the increased groundwater contamination from continued use of these units. 

This conclusion is further buttressed by the fact that during this interim period the risks 

associated with allowing these units to continue to receive CCR are mitigated by all of the other 

requirements of the rule with which the facility must continue to comply, including the 

requirements to continue groundwater monitoring and corrective action. Under §257.103(a)(1), 

a CCR unit that would otherwise be required to cease receiving CCR under §257.101(a), (b)(1), 

or (d), may continue to receive CCR provided the owner or operator certifies that the CCR 

generated at that facility must continue to be managed in that unit due to the absence of 

alternative disposal capacity both on-site and off-site. The rule also requires the owner or 

operator to document this claim and the claim must be based on the real absence of an alternative 

and not justified based on the costs or inconvenience of alternative disposal capacity. 

§257.103(a)(1)(i). The owner or operator must also remain in compliance with all other 

requirements of today’s rule, including the requirement to take any necessary corrective action. 

§257.103(a)(1)(ii). Because this alternative is only available as long as the absence of disposal 

capacity exists, the owner or operator must document its efforts to obtain additional capacity. If 

any additional capacity is identified, the owner or operator must arrange to use it as soon as it 

feasible. §257.103(a)(1)(iii). The owner or operator is also required to prepare an annual 
Document submitted to conclude E.O.12866 Review

443

progress report documenting the continued absence of disposal capacity and must also document 

the progress made toward developing alternative capacity. §257.103(a)(1)(iv).

Once alternative disposal capacity is available, the CCR unit subject to this section must 

cease receiving CCR and must initiate closure following the timeframes in §257.102(e) and (f). 

Finally, if the owner or operator has not identified alternative capacity within 5 years after the 

initial certification the CCR unit subject to this section must cease receiving CCR and must 

initiate closure following the timeframes in §257.102(e) and (f). As discussed elsewhere in this 

preamble, several commenters provided information to document the length of time needed to 

obtain additional capacity. Based on this information, the 5 year timeframe provided for under 

this alternative is expected to provide sufficient time to obtain alternative disposal capacity and 

to avoid the consequences of a forced immediate closure of a power plant.

2. Permanent cessation of a coal-fired boiler by a date certain. (§257.103(b)).

Under this provision, the Agency addresses the circumstance where a facility’s only 

disposal capacity, both on-site and off-site, is in a CCR unit that has triggered the closure 

requirements in §257.101(a), (b)(1), or (d), but the owner or operator of coal-fired power plant 

has decided to permanently cease operation of that plant within one of two timeframes specified 

in the regulation. For the same reasons discussed immediately above, EPA has concluded that 

the provisions of §257.103(b) represent the most reasonable balance between the competing 

risks.

Additionally, EPA anticipates that some owners or operators will decide to permanently 

cease operation of a coal-fired power plant in response to the combined effects of new and/or 

existing statutory or regulatory requirements promulgated under the Clean Air Act and under the 

Clean Water Act (e.g. the proposed Effluent Limitations Guidelines and Standards for the Steam 
Document submitted to conclude E.O.12866 Review

444

Electric Power Generating Point Source Category. See 78 FR 34442), in combination with 

market dynamics. As discussed earlier in this preamble, RCRA section 1006(b) directs EPA to 

integrate the provisions of RCRA for purposes of administration and enforcement and to avoid 

duplication, to the maximum extent practicable, with the appropriate provisions of other EPA 

statutes, including the CAA and the CWA. As noted earlier, section 1006(b) conditions EPA’s 

authority to reduce or eliminate RCRA requirements on the Agency’s ability to demonstrate that 

the integration meets RCRA’s protectiveness mandate (42 U.S.C. 6005(b)(1)). See Chemical 

Waste Management v. EPA, 976 F.2d 2, 23, 25 (D.C. Cir.1992). The provisions of §257.103(b) 

are fully consistent with the direction in section 1006(b) to account for the provisions of other 

EPA statutes which may lead an owner or operator to close a coal-fired power plant.

EPA has also concluded that the provisions of §257.103(b) meet RCRA’s protectiveness 

mandate. As stated above, EPA recognizes that there are long-term risks to human health and 

the environment, as demonstrated throughout this preamble, from a leaking CCR unit and those 

risks justify requiring those units to either meet the federal criteria established in today’s rule or 

close. However, the risks associated with allowing these units to continue to receive CCR are 

mitigated by the requirement that the facility must comply with all other requirements of the rule, 

including initiating ground water monitoring and corrective action where necessary. And a 

critical factor is that facilities that choose to rely on this alternative will be required to complete

closure of their disposal unit in an expedited timeframe. Thus, the risks from these units will be 

fully addressed sooner. Consequently, while over the short term the risks will be higher, overall, 

the risks will be at least equivalent to, or potentially lower than if the CCR unit had closed in 

accordance with the normal closure timeframes.
Document submitted to conclude E.O.12866 Review

445

Under §257.103(b)(1), a CCR unit that would otherwise be required to cease receiving 

CCR under §257.101(a), (b)(1), or (d), may continue to receive CCR provided the owner or 

operator of the facility certifies that the facility will cease operation of the coal-fired boilers 

within the timeframes specified in paragraphs (b)(2) through (b)(4) and that the CCR generated 

at that facility (before the plant ceases to operate) must continue to be managed in that unit due 

to the absence of alternative disposal capacity both on-site and off-site. The rule also requires 

the owner or operator to document the facts that support this claim. The regulation specifies that 

the claim must be based on the real absence of alternative disposal capacity, and not justified 

based on the costs or inconvenience of alternative disposal capacity. §257.103(b)(1)(i). The 

owner or operator must also remain in compliance with all other requirements of today’s rule, 

including the requirement to take any necessary corrective action. §257.103(b)(1)(ii). The 

owner or operator is also required to prepare an annual progress report documenting the 

continued absence of disposal capacity and must also document the progress made toward the 

closing of the coal-fired boiler. §257.103(b)(1)(iii).

Under §257.103(b)(1), the owner or operator does not need to demonstrate any efforts to 

develop alternative capacity because of the impending closure of the power plant itself.

Consistent with the general timeframes provided for the closure of CCR surface 

impoundments, EPA has established different timeframes based on the size of the CCR unit. 

Under §257.103(b)(2), where the disposal unit is a CCR surface impoundment 40 acres or 

smaller in size, the coal-fired boiler must cease operation and the disposal unit must have 

completed closure within 8.5 years of the publication date of the rule. Where the disposal unit is 

a CCR surface impoundment larger than 40 acres in size, the coal-fired boiler must cease 

operation and the disposal unit must have completed closure within 13.5 years of the publication 
Document submitted to conclude E.O.12866 Review

446

date of the rule. §257.103(b)(3). Finally, under §257.103(b)(4), where the disposal unit is a CCR 

landfill, the coal-fired boiler must cease operation and the disposal unit must have completed 

closure within 6 years of the publication date of the rule. These timeframes were selected to 

ensure that closure of these units will be completed in a measurably shorter timeframe, and that 

overall the risks will be lower, or at least equivalent to, the level of risk that would be achieved 

under the rule’s “standard” closure provisions.

5. Notation on the Deed to Property

The proposed rule would have required, following closure of the CCR unit, the 

owner or operator to record a notation on the deed or some other instrument normally examined 

during a title search. This notation would notify any potential purchaser in perpetuity that the 

property has been used a CCR landfill or CCR surface impoundment and that use of the land is 

restricted under the rule’s post-closure care provisions. After the notation was completed, the 

proposed rule would have required the owner or operator to notify the state that the notation has 

been recorded and a copy has been placed in the facility’s operating record and on its publicly 

accessible internet site. In addition, the Agency solicited public comment on adding a provision 

to the rule to allow removal of the deed notation once all CCR are removed from the CCR unit, 

and notification is provided to the state of this action. The EPA solicited comment on this 

potential approach as a way to create a further incentive for clean closure of the facility. 75 FR 

at 35208-09. The proposal further encouraged commenters who are interested in supporting such 

an option to suggest alternatives to state oversight to provide for facility accountability.

EPA received few public comments on the proposed requirement to record a deed 

notation to the property (or some other instrument that is normally examined during title search). 

One commenter provided general support for the proposed requirement to record a deed notation 
Document submitted to conclude E.O.12866 Review

447

to the property. Another commenter urged EPA to ensure that any deed notation requirements 

should not interfere or conflict with existing state property laws that provide for environmental 

covenants.

EPA did receive several comments in response to the Agency’s solicitation of 

comment on adding a provision to the rule to allow removal of the deed notation when all CCR 

are removed from the facility, and notification is provided to the state of this action. One 

commenter supported the addition of this provision, stating that the licensure requirements of the 

Professional Engineer provide an assurance of integrity because the Professional Engineer would 

be required to verify that closure has been completed in accordance with the closure plan. This 

commenter also stated that it would be sufficient to allow removal of a deed notation upon an 

application to the state agency supported by a declaration of a licensed professional, subject to 

state agency review and approval. Another commenter supported providing the incentive for 

clean closure and allowing the facility to demonstrate the “cleanliness of the closure.” The 

commenter also recommended that the information provided by the facility should be followed 

by a review from an independent third party with knowledge of the industry and associated 

environmental issues.

After considering comments, the final rule requires an owner or operator to record 

a notation on the deed or some other instrument normally examined during a title search. This 

notation notifies any potential purchaser in perpetuity that the property has been used a CCR 

landfill or CCR surface impoundment and that use of the land is restricted under the rule’s postclosure care provisions. See §257.102(i). In response to the commenter that urged EPA to 

ensure that any deed notation requirements should not interfere or conflict with existing state 

property laws, the Agency has no information that the proposed requirement would create such a 
Document submitted to conclude E.O.12866 Review

448

conflict. In addition, the commenter did not provide any information or suggest that EPA’s 

proposed approach would actually interfere or conflict with existing state property laws. 

Therefore, the Agency is finalizing the deed notation requirement as proposed.

In addition, regarding the Agency’s solicitation of comment on adding a provision 

to the rule to allow removal of the deed notation when all CCR are removed from the facility, as 

discussed in Unit VI.M.2 of this preamble, the final rule adopts the proposal to allow the owner 

or operator to remove the deed notation required under §257.102(i)(4), upon certification that 

clean closure has been completed. The rationale for this decision is discussed in that unit of the 

preamble.

6. Notification of Intent to Close and Certification of Closure Completion

The Agency proposed to require owners or operators to notify the state that a 

notice of intent to close a CCR unit has been placed in the facility’s operating record and on the 

publicly accessible internet site. This notification had to be completed prior to beginning closure 

of the CCR unit. Following closure of a CCR unit, the proposed rule would also have required 

the owner or operator to obtain a certification from an independent registered professional 

engineer verifying that closure has been completed in accordance with the written closure plan. 

As proposed, this certification would be placed in the facility’s operating record and on the 

publicly accessible internet site.

The Agency received no public comments on the proposed requirements to develop a 

notification of intent to close or the certification of completion of closure. Therefore, the 

Agency is finalizing these requirements as proposed. See §257.102(g) and (h).

7. Post-Closure Care Plan
Document submitted to conclude E.O.12866 Review

449

The Agency proposed to require that the owners or operators of CCR landfills and 

CCR surface impoundments prepare a written post-closure care plan describing how the CCR 

unit would be maintained after closure. See proposed §257.101(c). The proposal also identified 

the minimum information necessary to include in the post-closure care plan. This information 

included: (1) a description of the monitoring and maintenance activities for the CCR unit and the 

frequency at which these activities would be performed; (2) the name, address, and telephone 

number of the person or office to contact about the facility during the post-closure care period; 

and (3) a description of the planned uses of the property during the post-closure care period.

The proposed rule further provided that the post-closure use of the property shall not 

disturb the integrity of the final cover, liner(s), or any other components of the containment 

system, or the function of the post-closure monitoring systems unless necessary to comply with 

the requirements of the rule. The proposal would have allowed a disturbance if the owner or 

operator of the CCR unit demonstrated that disturbance of the final cover, liner, or other 

component of the containment system, including any removal of CCR, would not increase the 

potential threat to human health or the environment. A professional engineer would have been 

required to certify such a demonstration.

The Agency received no significant comments on the proposed post-closure care 

requirements. The Agency’s responses to these comments are addressed in the closure comment 

response document, which is available in the rulemaking docket. Therefore, the Agency is 

finalizing these requirements substantially as proposed. See §257.102(g) and (h).

8. Post-Closure Care Activities

Following closure of a CCR landfill or CCR surface impoundment, EPA proposed 

that the owner or operator would be required to conduct post-closure care of the closed unit. At 
Document submitted to conclude E.O.12866 Review

450

a minimum, the proposal would have required the owner or operator to conduct at least the 

following: (1) maintain the integrity and effectiveness of any final cover, including making 

repairs to the final cover to correct the effects of settlement, subsidence, erosion, or other events, 

and preventing run-on and run-off from eroding or otherwise damaging the final cover; (2) 

maintain the integrity and effectiveness of the leachate collection and removal system and 

operating the leachate collection and removal system in accordance with applicable requirements 

under the design criteria for such systems; and (3) maintain the groundwater monitoring system 

in accordance with applicable requirements under the groundwater monitoring and corrective 

action rule provisions.

EPA received few public comments on the proposed activities to conduct during the postclosure care period. These commenters were supportive of the activities and specifically urged 

the rule to require the monitoring of groundwater throughout the post-closure care period. The 

Agency received no comments opposing the proposed post-closure care activities. Therefore, 

EPA is finalizing the same post-closure care activities in this rule. See §257.104(b). In addition, 

consistent with the proposal, the rule clarifies that certain CCR units are not subject to these 

post-closure care activities. Specifically, owners or operators that elect to close a CCR unit by 

removing CCR (i.e., clean close the CCR unit) are not subject to any post-closure care 

requirements. See §257.104(a)(2) and Unit M.2 of this preamble. In addition, owners or 

operators of inactive CCR surface impoundments that elect to complete closure of the unit within 

30 months of the rule’s effective date are not subject to any post-closure care requirements. See 

§257.104(a)(3).

9. Length of Post-Closure Care Period
Document submitted to conclude E.O.12866 Review

451

The Agency proposed that the owner or operator of a CCR unit conduct postclosure care for 30 years. EPA also proposed to allow utilities to conduct post-closure care for a 

decreased length of time if the owner or operator demonstrates that the reduced period is 

sufficient to protect human health and the environment. The owner or operator would have been 

required to have this demonstration certified by a professional engineer, in addition to complying 

with all of the notification and posting requirements under the proposed rule. The proposed rule 

would also have allowed an increase in the post-closure care period if the owner or operator of 

the CCR unit determined that it is necessary to protect human health and the environment. EPA 

also recognized in the proposed rule that state oversight can be critical to ensure that post-closure 

care is conducted for the length of time necessary to protect human health and the environment; 

however the Agency also recognized that there is no set length of time for post-closure care that 

will be appropriate for all possible sites, and all possible conditions. Therefore, EPA solicited 

comment on alternative methods to account for different conditions, yet still provide methods of 

oversight to assure facility accountability.

Some commenters supported the proposed approach because it provided 

flexibility to increase or decrease the post-closure care period of 30 years. EPA also received 

comments from a number of states documenting the current state requirements; some states 

require a post-closure care period of less than 30 years, some require 30 years, and one state 

currently requires 40 years for CCR units. Other commenters opposed the shortening of the 30-

year period without state involvement and approval.

After considering public comments, and in a departure from the proposed rule, the 

Agency is requiring that post-closure care be conducted for a minimum of 30 years. EPA is 

making this change due to the lack of guaranteed state oversight for this rule. The Agency has 
Document submitted to conclude E.O.12866 Review

452

concluded that providing the owner or operator the flexibility to shorten the post-closure care 

period is no longer appropriate, particularly given the flexibility being provided for the selection 

of a final cover system or alternative final cover system. As discussed in Unit M.3 above, the 

information available to the Agency supports the need to proceed cautiously. By not allowing 

the post-closure care period to be shortened, EPA better ensures that the final cover system will 

be properly maintained. In addition, a mandatory 30 year period ensures that if problems do 

arise with respect to a final cover system, the groundwater monitoring and corrective action 

provisions of the rule will detect and address any releases from the CCR unit, at least during the 

post-closure care period.

10. Notification of Completion of Post-Closure Care Period

The Agency proposed to require owners or operators of CCR units to notify the 

state that a notice of completion of the post-closure care period has been placed in the facility’s 

operating record and on the publicly accessible internet site. The proposed approach would have 

required the owner or operator to obtain a certification from an independent registered 

professional engineer verifying that post-closure care has been completed in accordance with the 

written post-closure care plan.

The Agency received no public comments on the proposed requirement to develop a notification 

of completion of the post-closure care period. Therefore, the Agency is finalizing these 

requirements as proposed. See §257.104(e).

M. Recordkeeping, Notification and Posting of Information to the Internet

In response to EPA’s lack of authority to require a state permit program or to oversee 

state programs, EPA has sought to enhance the protectiveness of the regulatory requirements by 

providing for state and public notifications of the third party certifications, as well as requiring a 
Document submitted to conclude E.O.12866 Review

453

robust set of other information that documents the decisions made or actions taken to comply 

with the technical requirements of the rule. Consistent with the proposed rule, owners or 

operators of CCR units are required to document how the various provisions of the rule have 

been met by placing information (e.g., plans, records, notifications, reports) in the operating 

record and providing notification of these actions to the State Director/or appropriate Tribal 

authority. The owner or operator is also required to establish and maintain a publicly accessible 

internet site that posts documentation that has, in many instances, also been entered into the 

operating record. The owner or operator is required to maintain a copy of the current Emergency 

Action Plan, the current fugitive dust control plan, and the current written closure plan as long as 

the facility remains active. EPA believes that the establishment and maintenance of this 

information in both the operating record and on a publicly accessible internet site is appropriate 

so as to allow states and citizens access to all of the information necessary to show that the rule 

has been implemented in accordance with the regulatory requirements.

With regard to the specific recordkeeping and reporting requirements outlined in the 

proposal, the Agency received very little comment. Commenters were primarily concerned not 

with the specific recordkeeping requirements but rather how the recordkeeping requirements 

aligned with the overall approach of the RCRA subtitle D regulatory scheme. These comments 

and the Agency’s responses are discussed in Unit V of this preamble.

The combined mechanisms of recordkeeping, notifications, and maintaining a publicly 

accessible internet site will serve to provide interested parties with the information necessary to 

determine whether the owner or operator is implementing and is operating in accordance with the 

requirements of the rule. As stated in the proposal and reiterated here, EPA believes that it 

cannot conclude that the RCRA subtitle D regulations will ensure there is no reasonable 
Document submitted to conclude E.O.12866 Review

454

probability of adverse effects on health or the environment, unless there are mechanisms for 

states and citizens to monitor the situation, such as when groundwater monitoring shows 

exceedances above the groundwater protection standard specified in the rule, so they can 

determine when intervention is appropriate. EPA also believes that the recordkeeping and 

notification requirements will minimize the danger of owners or operators abusing the selfimplementing system being established in this rule through increased transparency and by 

facilitating the citizen suit enforcement provisions applicable to the rule. 

In contrast to the proposed rule, the Agency has identified for ease of implementation 

each recordkeeping, notification and internet posting required in this rule. The proceeding 

section provides a summary of the requirements for each reporting mechanism. 

1. Recordkeeping Requirements

This rule requires the owner or operator of a CCR landfill or CCR surface impoundment 

and any lateral expansion to maintain files of all required information (e.g., demonstrations, 

plans, notifications, and reports) that supports the implementation of this rule in an operating 

record located at the facility. Each file must be maintained in the operating record for a period of 

at least five years following submittal of the file into the operating record. In certain instances,

however, files must be maintained until the CCR unit completes closure. For example, the initial 

and periodic structural stability assessments as required under section § 257.73(d) and § 

257.74(d) must be maintained for five years consistent with the timeframe for periodic 

reassessments. Whereas, information on the construction of a CCR surface impoundment must 

be maintained until the CCR unit completes closure (see 257.73(c) and 257.102.) These time 

frames are generally consistent with the time frames required for maintaining hazardous waste 
Document submitted to conclude E.O.12866 Review

455

compliance records under subtitle C of RCRA and with the timeframes outlined in the proposed 

subtitle C option for the regulation of CCR. (See specifically 40 CFR 264.73 and 265.73.)

Owners or operators with more than one CCR unit may elect to consolidate all files into 

one operating record provided that each unit is identified and files for that unit are maintained 

separately in different sections of the operating record. The owner or operator of the CCR unit 

must place files documenting compliance with the location restrictions; design criteria; operating 

criteria; groundwater monitoring and corrective action; closure and post closure care, into the 

operating record, with the specific documentation requirements found in § 257.105. In the 

development of this final rule, the Agency has included in the regulatory language a 

comprehensive listing of each recordkeeping and notification required by the rule. The Agency 

anticipates that this effort will facilitate owners or operators efforts in complying with the 

reporting provisions of the rule, and will provide other interested parties with a guide to the 

reporting provisions of the rule. 

2. Notification Requirements

As previously discussed, owners or operators are required to notify State Directors and/or 

the appropriate Tribal authority when specific documentation has been placed in the operating 

record and on the owner or operator’s publicly accessible website. In most instances these 

notifications must be certified by a qualified professional engineer and may, in certain instances 

will be accompanied with additional information and or data supporting the notification. For 

example under § 257.106(f)(1), within 60 days of commencing construction of a new CCR unit, 

a notification of the availability of the design criteria specified under § 257.105(f)(1) or (f)(3) in 

the operating record and on the owner or operator’s publicly accessible internet site. If however, 

the owner or operator of the CCR units elects to install an alternative composite liner, the owner 
Document submitted to conclude E.O.12866 Review

456

or operator must also submit to the State Director and/or appropriate Tribal authority a copy of 

the alternative composite liner design which has been certified by a qualified professional 

engineer. 

Notification requirements can be found in § 257.106, and are required for location 

criteria, design criteria, operating criteria, groundwater monitoring and corrective action and 

closure and post closure care. 

3. Publicly Accessible Internet Site Requirements

The Agency is finalizing, as proposed a requirement for owners and operators of 

any CCR unit to establish and maintain a publicly accessible internet site, titled “CCR Rule 

Compliance Data and Information.” As with the operating record, owners or operators that 

maintain multiple CCR units may elect to use one internet site in order to comply with these 

requirements, provided that the website clearly and distinctly identifies information from each of 

the CCR units by name and location. Unless provided otherwise in the rule, information posted 

to the internet site must be available for a period no less than three years from the initial posting 

date. Posting of information must be completed no later than 30 days from submittal of the 

information to the operating record. This timeframe is consistent with the notification 

requirements of the rule. As with the other criteria in this section, internet postings are required 

for various elements identified in the following sections: location restrictions; design criteria; 

operating criteria; groundwater monitoring and corrective action; closure and post closure care.

These requirements are enforceable by citizen suits.

VII. Summary of Major Differences between the Proposed and Final Rules

The basic regulatory framework outlined in the proposed rule under the Subtitle D option, 

is being adopted in this final rule for the regulation of CCR landfills and CCR surface 
Document submitted to conclude E.O.12866 Review

457

impoundments and any lateral expansion. However, as discussed in Unit VI, the Agency has 

made a number of revisions to several of the provisions in the proposed rule, including (1) the 

timeframes for closure; (2) locations restrictions – placement above the uppermost aquifer; (3) 

the use of an alternative composite liner design; (4) revisions to align the structural stability 

criteria with the experience and data generated by the Assessment Program; and (5) air criteria. 

These changes have been made in response to public comments and additional information 

collected and analyses conducted by EPA in the course of responding to those comments. These 

are discussed in greater detail below. Under the proposed rule, all new CCR landfills and all 

CCR surface impoundments that had not completed closure would be required to retrofit to a 

composite liner or close within five years. However, after reviewing comments and further 

evaluation, the Agency has concluded that this regulatory approach was unnecessary in light of 

the protections afforded by the other technical provisions of the rule (e.g., groundwater 

monitoring, corrective action). In the final rule, EPA is allowing unlined CCR surface 

impoundments to continue to operate for the remainder of the active life, provided that the 

facility documents through groundwater monitoring that the CCR surface impoundment is not 

contaminating groundwater. However, if groundwater monitoring at the facility demonstrates 

that the unlined CCR surface impoundment has exceeded any groundwater protection standard,

the owner or operator must initiate corrective action, and either remove all CCR from the unit 

and install a composite liner (i.e., “retrofit”) or close within five years. In a departure from the 

proposed rule, CCR surface impoundments less than 40 acres may receive one two-year 

extension, providing for a maximum of seven years to complete closure. Units greater than 40 

acres may receive up to five two-year extensions providing a maximum of 15 years to complete 
Document submitted to conclude E.O.12866 Review

458

closure. These units are also eligible for alternative closure timeframes to account for site 

specific operational constraints.

In addition, under the proposed rule, CCR surface impoundments that had not closed in 

accordance with the rule would be subject to all the provisions of the rule. After further 

evaluation, EPA has revised the provision to allow an inactive CCR surface impoundment three 

years from publication of the rule in the Federal Register to complete closure. Owners or 

operators of inactive CCR surface impoundments that have not completed closure within this 

timeframe are subject to all the applicable requirements of the rule.

In response to comment and upon further evaluation the Agency is amending the location 

restriction relating to the placement of the CCR unit above the natural water table. Under the 

proposal, new landfills, any CCR surface impoundment, and all lateral expansions would have 

been required to have a base located a minimum of two feet above the upper limit of the natural 

water table. In the final rule, the Agency has amended this requirement to require that new CCR 

landfills and all CCR surface impoundments, and all lateral expansions be constructed with a 

base no less than 1.52 meters (five feet) above the uppermost aquifer or must demonstrate that 

there will not be an intermittent, recurring, or sustained hydraulic connection between any 

portion of the base of the CCR unit and the uppermost aquifer due to normal fluctuations in 

groundwater elevations (including the seasonal high water table.) EPA has made this change in 

response to comments and further evaluation demonstrating that this standard is the minimum 

distance necessary to demonstrate that no reasonable probability of adverse effects on human 

health and the environment will occur.

EPA proposed to require all new CCR landfills, CCR surface impoundments and any 

lateral expansion to be constructed with a composite liner. A composite liner was defined as a 
Document submitted to conclude E.O.12866 Review

459

system consisting of two components; the upper component consisting of a minimum 30-mil 

flexible membrane liner (FML) and the lower component consisting of at least two feet of 

compacted soil. Based on public comments and further evaluation, the Agency is finalizing a 

new requirement that allows an owner or operator to install an alternative composite liner 

provided it meets the performance standard established in the rule. EPA has concluded that this 

alternative composite liner affords the same protection to groundwater resources as a composite 

liner.

Under the proposed rule, all CCR landfills and CCR surface impoundments would have 

been required to manage fugitive dusts in a manner not to exceed 35 ug/m3. The proposal also 

required owners or operators to control the wind dispersal of dusts consistent with the standard, 

and to document the measures taken to comply with the requirements. In response to comments 

and upon further evaluation, the Agency has removed the numerical standard of 35ug/m3 from 

the rule and is establishing a performance standard for fugitive dust control. This standard 

requires owners or operators of any CCR unit to adopt measures that will effectively minimize 

CCR from becoming airborne at the facility. The Agency considers this standard to be generally 

consistent the proposed rule with the added advantage of allowing for flexibility in achieving 

compliance. The owner or operator must also prepare an annual CCR fugitive dust control report 

that describes action taken by the owner or operator to control CCR fugitive dust and to present a 

record of all citizen complaints during the previous year, as well as a summary of the corrective 

action measures taken.

VIII. Implementation Timeframes for Minimum National Criteria and Coordination with 

Steam Electric ELG Rule. 
Document submitted to conclude E.O.12866 Review

460

The final rule generally establishes time frames for the technical criteria based on the 

amount of time determined to be necessary to implement the requirements (e.g., installing the 

groundwater monitoring wells). In establishing these time frames, EPA also accounted for other 

Agency rulemakings that may affect owners or operators of CCR units, namely the Effluent 

Limitations Guidelines and Standards for the Steam Electric Power Generating Point Source 

Category (ELG) (78 FR 34432 (June 7, 2013)) and the Carbon Pollution Emission Guidelines for 

Existing Stationary Sources: Electric Utility Generating Units (Clean Power Plan) (79 FR 34830 

(June 18, 2014)). Specifically, the implementation timeframes in this rule will not require 

owners or operators of CCR units to make decisions about those CCR units without first 

understanding the implications that such decisions would have for meeting the requirements of 

each rule. For example, this final rule requires the closure and post-closure plans to be prepared 

following the anticipated publication of the ELG and Clean Power Plan final rules so that owners 

or operators of CCR units can take into consideration those final rules as they prepare the closure 

and post-closure care plans.

This is also particularly true in the situation where the minimum criteria in the CCR rule 

could potentially require a surface impoundment to either undergo RCRA closure or retrofit with 

a composite liner. A decision on what action to take with that unit may ultimately be directly 

influenced by the requirements of the ELG rule; for example, if the final ELG rule requires a 

conversion to dry handing of fly ash, then it may not make economic sense for an electric utility 

to retrofit a surface impoundment that contains wet-handled fly ash since it would be required to 

cease that practice under the ELG rule. Thus, under the final timeframes in this rule, any such 

decision will not have to be made by the owner or operator of a CCR unit until well after the 

ELG rule is final and the regulatory requirements are well understood. In this example, the 
Document submitted to conclude E.O.12866 Review

461

earliest date that a CCR surface impoundment may be triggered into a retrofit or closure decision 

is approximately February 2017 (the exact date would be 24 months following publication of this 

final rule), which would apply to a CCR surface impoundment that fails to achieve minimum 

safety factors for the CCR unit. This is due to the fact that the owner or operator must complete 

the initial safety factor assessment within 18 months of the publication of this rule plus an 

additional six months to initiate closure of the CCR unit if the minimum factors or safety are not 

achieved. The ELG rule is scheduled to be finalized in September 2015 and its effective date is 

60 days following its publication. Thus, there is ample time for the owners and operators of 

CCR units to understand the requirements of both regulations and to make the appropriate 

business decisions.

Table 1 below summarizes the implementation timeframes for the minimum criteria for 

existing CCR surface impoundments being promulgated in this rule. Table 2 provides a similar 

summary for existing CCR landfills.

Table 1.—Implementation Timeframes for the Minimum Criteria for Existing CCR 

Surface Impoundments

Requirement

Implementation 

Timeframe (Number of 

Months after Publication 

of Rule)

Description of Requirement to be 

Completed

Location Restrictions 

(§257.60 - §257.64)

42 months - Complete demonstration for 

placement above the uppermost 

aquifer Complete demonstrations for 

wetlands, fault areas, seismic impact 

zones, and unstable areas

Design Criteria 

(§257.71)

18 months - Document whether CCR unit is 

either a lined or unlined CCR 

surface impoundment

Structural Integrity

(§257.73)

8 months

18 months

- Install permanent marker

- Compile a history of construction,

complete initial hazard potential 

classification assessment, initial 
Document submitted to conclude E.O.12866 Review

462

24 months

structural stability assessment, and 

initial safety factor assessment

- Prepare emergency action plan

Air Criteria

(§257.80)

6 months - Prepare fugitive dust control plan

Hydrologic and 

Hydraulic Capacity

(§257.82)

18 months - Prepare initial inflow design flood 

control system plan

Inspections

(§257.83)

6 months

6 months

9 months

- Initiate weekly inspections of the 

CCR unit

- Initiate monthly monitoring of 

CCR unit instrumentation

- Complete the initial annual 

inspection of the CCR unit

Groundwater Monitoring 

and Corrective Action

(§257.90 - §257.98)

30 months - Install the groundwater monitoring 

system; develop the groundwater 

sampling and analysis program; 

initiate the detection monitoring 

program; and begin evaluating the 

groundwater monitoring data for 

statistically significant increases 

over background levels

Closure and Post-Closure 

Care 

(§257.103 - §257.104)

18 months - Prepare written closure and postclosure care plans

Recordkeeping, 

Notification, and Internet 

Requirements

(§257.105 - §257.107)

6 months - Conduct required recordkeeping

- Provide required notifications

- Establish CCR website

Table 2.—Implementation Timeframes for the Minimum Criteria for Existing CCR 

Landfills

Requirement

Implementation 

Timeframe (Number of 

Months after Publication 

of Rule)

Description of Requirement to be 

Completed

Location Restrictions 

(§257.64)

42 months - Complete demonstration for 

unstable areas

Air Criteria

(§257.80)

6 months - Prepare fugitive dust control plan

Run-On and Run-Off 

Controls

(§257.81)

18 months - Prepare initial run-on and run-off 

control system plan

Inspections

(§257.83)

6 months - Initiate weekly inspections of the 

CCR unit
Document submitted to conclude E.O.12866 Review

463

9 months - Complete the initial annual 

inspection of the CCR unit

Groundwater Monitoring 

and Corrective Action

(§257.90 - §257.98)

30 months - Install the groundwater monitoring 

system; develop the groundwater 

sampling and analysis program; 

initiate the detection monitoring 

program; and begin evaluating the 

groundwater monitoring data for 

statistically significant increases 

over background levels

Closure and Post-Closure 

Care

(§257.103 - §257.104)

18 months - Prepare written closure and postclosure care plans

Recordkeeping, 

Notification, and Internet 

Requirements

(§257.105 - §257.107)

6 months - Conduct required recordkeeping

- Provide required notifications

- Establish CCR website

IX. Implementation of the Minimum Federal Criteria and State Solid Waste 

Management Plans

As explained earlier in this notice, the final regulations EPA is promulgating under 

RCRA subtitle D impose minimum federal criteria with which CCR units must comply without 

any additional action by a State or federal regulator. As discussed previously in today’s notice, 

under the provisions of subtitle D applicable to solid waste, States are not required to adopt or 

implement these regulations, to develop a permit program, or submit a program covering these 

units to EPA for approval and there is no mechanism for EPA to officially approve or authorize a 

State program to operate “in lieu of” the federal regulations. 

EPA has, however, received numerous comments regarding the potential implementation 

challenges that this statutory and resulting regulatory structure may pose, particularly in States 

that already have a comprehensive regulatory program governing CCR units. These concerns 

include the fact that facilities may need to comply with two sets of potentially differing 

regulations, perhaps resulting in confusion for the regulated community and the general public, 
Document submitted to conclude E.O.12866 Review

464

and also potentially resulting in inconsistent results from citizens seeking enforcement of the 

criteria. The commenters were also concerned and that there is no explicit mechanism for EPA 

to officially approve a state program (as there is in subtitle C or in the municipal solid waste 

provisions of subtitle D). In addition, in States without a current formal program for overseeing 

CCR landfills and surface impoundments at coal fired electric utilities, stakeholders have 

expressed a preference for a state mechanism for implementing the federal requirements. 

Finally, many stakeholders expressed a strong preference for a permit program with its 

opportunities for public input and transparency.

Moreover, EPA recognizes the critical role that our State partners play in implementation 

and ensuring compliance with environmental regulations. This is particularly important in 

complex situations, such as presented by CCR landfills and surface impoundments that involve 

corrective action and requirements and timelines for closure of units. EPA expects that States 

will be active partners in overseeing the regulation of CCR landfills and CCR surface 

impoundments, and has adopted a number of provisions to ensure that States have the 

information necessary to undertake this role. First, the final regulations require owners or 

operators of regulated CCR units to notify the State of actions taken to comply with the 

requirements of the rule (see § 257.106). Facilities will also be required to maintain a publicly 

accessible internet site that will document the facility’s compliance with the requirements of the 

rule; states (along with other members of the public) will be able to access this site to monitor 

facility activities (see § 257.107). (For a detailed discussion of these requirements, please see 

Unit VI.M.)

In order to ease implementation the regulatory requirements for CCR landfills and CCR 

surface impoundments, EPA strongly encourages the States to adopt at least the federal 
Document submitted to conclude E.O.12866 Review

465

minimum criteria into their regulations. EPA recognizes that some States have already adopted 

requirements that go beyond the minimum federal requirements; for example, some States 

currently impose financial assurance requirements for CCR units, and require a permit for some 

or all of these units. This rule will not affect these State requirements. The federal criteria 

promulgated today are minimum requirements and do not preclude States’ from adopting more 

stringent requirements where they deem to be appropriate. 

As noted above, commenters on the proposal voiced concerns that because EPA does not 

have the authority to approve a State program under subtitle D of RCRA, there is no document in 

which EPA formally provides its judgment that a State solid waste program substantially 

incorporates the minimum federal criteria. However, a mechanism for this has been available for 

many years through the Solid Waste Management Planning process already in the regulations at 

40 CFR Part 256 “Guidelines for Development and Implementation of State Solid Waste 

Management Plans.” This process, designed early in the development of the waste management 

infrastructure, was structured to encourage States to effectively plan for and manage their solid 

wastes, including upgrading or closing any units that were considered “open dumps” through the 

development of Solid Waste Management Plans (SWMPs or plans). Currently most States have 

SWMPs that have previously been submitted to and approved by EPA. EPA strongly 

recommends that States take advantage of this process by revising their SWMPs to address the 

issuance of the revised federal requirements in this final rule, and to submit revisions of these 

plans to EPA for review, using the provisions contained in 40 CFR Part 256. To be clear, EPA is 

not suggesting that States revise their entire SWMPs, but only that States revise their plans to 

address the revised federal requirements being promulgated today. EPA would then review and 

approve the revised SWMPs provided they demonstrate that the minimum federal requirements 
Document submitted to conclude E.O.12866 Review

466

in this final rule will be met. In this way, EPAs approval of a revised SWMP signals EPA’s 

opinion that the State SWMP meets the minimum federal criteria. 

As noted above, the part 256 regulations established the system for the development and 

approval of initial SWMPs as well as their revisions. For the convenience of the reader, we 

describe these regulations in the following paragraphs. The regulations lay out a series of 

requirements that a plan must meet to be approved, as well as a number of recommendations that 

should also be reflected in the solid waste management plan. E.g., 40 C.F.R. §§ 256.01-256.04 

and 256.20 – 256.27. For example, section 256.02 sets out the scope of the SWMPs, requiring 

that the plans address “all solid waste in the State that poses potential adverse effects on public 

health or the environment or provides an opportunity for resource conservation or resource 

recovery.” The regulations also specify that the plan must require that all solid waste shall be 

disposed of in “sanitary landfills,”--i.e., units that meet any federal requirements promulgated 

under RCRA section 4004(a)--or otherwise disposed of in an environmentally sound manner. 40 

C.F.R. §256.01(a)(2). The plan must also prohibit the establishment of new open dumps, and 

provide for the closing or upgrading of all existing open dumps within the State, pursuant to the 

requirements of RCRA section 4005. 40 C.F.R. §256.01(a)(2)-(3). State plans must also “set 

forth an orderly and manageable process for achieving the objectives of the Act and meeting the 

requirements of these guidelines.” 40 C.F.R. §256.02(d). The regulations further specify that the 

plan “shall describe as specifically as possible the activities to be undertaken, including detailed 

schedules and milestones.” Id. 

The Part 256 regulations further require a SWMP to identify the state’s legal authorities, 

and regulatory powers, including any revisions that may be necessary to implement the plan. 40 

C.F.R. §256.02(e). The plan must also identify and set out the responsibilities of state, local, and 
Document submitted to conclude E.O.12866 Review

467

regional authorities that will implement the state plan. 40 C.F.R. §256.10(a). Thus, the SWMP 

is the comprehensive compendium, developed and adopted with public participation, setting 

forth how solid waste is managed in a particular State. As such, SWMPs have been a key 

component of solid waste programs for many years. As stated above, states that have approved 

plans will only need to address these requirements for CCR landfills and surface impoundments.

In addition to the substantive requirements, the Part 256 regulations impose a number of 

procedural obligations. Before submission to EPA, the SWMP must be adopted by the State 

pursuant to State administrative processes and developed in accordance with the public 

participation requirements set out in § 256.60. In addition, all SWMPs were to contain 

procedures for revisions. 40 C.F.R. §256.03(e). EPA anticipates that States would rely on their 

existing procedures to revise their SWMPs to implement the new federal criteria. 

Currently, most states have approved SWMPs. These approvals were based on the 

requirements applicable to solid waste management that were in force at the time of approval. 

Now, because EPA is promulgating revised Federal criteria, the facilities that will be considered 

to be “sanitary landfills” and “open dumps” is changing. Thus, EPA expects that SWMPs in 

many states will need to be revised to account for these revised Federal requirements. Consistent 

with the provisions in section 256.01(a)(2)-(3) and with the requirement in section 256.03(e) that 

such plans are to be revised where necessary, in order to maintain approval of these plans EPA 

expects that States will revise their SWMPs to account for the promulgation of revised federal 

criteria for CCR landfills and surface impoundments. 

As fully explained later in this section, the plans are generally the best tool available for 

demonstrating how CCR disposal units will be regulated in a State, including how the State 

intends its state requirements to relate to the federal regulations. In addition, EPA anticipates 
Document submitted to conclude E.O.12866 Review

468

that the public participation processes will have substantial benefit, by involving all sectors of 

the community in addressing the management of CCR in a particular state. 

EPA believes that the revised SWMPs will have significant benefits and provide the best 

mechanism available to respond to the concerns expressed by commenters regarding the role of 

states in management of this waste. First, the revised plans will enable States to set out, as part 

of their overall solid waste program, how the State intends to regulate CCR landfills and surface 

impoundments; that is, these plans can demonstrate how, if at all, the State program has 

incorporated the minimum national criteria and can highlight those areas where the State 

regulations are more stringent than or otherwise go beyond the federal minimum criteria. For 

example, the plan can describe the actions the State will take to oversee CCR units, particularly 

those units undergoing closure or corrective action, and how the State intends to review or use 

the notices and other information pertaining to the units that the facility owners will be providing 

to the State (as required in the federal regulations). Providing this detail can greatly assist the 

regulated community to understand the regulatory structure under which they will be operating. 

It can also assist the general public in understanding the regulations and thereby their ability to 

industry’s monitor compliance with the rule. 

Second, substantial benefits will be gained through the public participation process 

required as part of revising the State plans. See 40 C.F.R § 256.60. At a minimum, these 

processes will promote greater awareness of the federal regulatory requirements, as well as how 

these fit into the overall context of solid waste management in the State, which will be very 

valuable as the new minimum criteria for CCR are implemented. In addition, these processes 

will provide the public and communities near CCR landfills and surface impoundments with an 

opportunity to participate in the decision making about how CCR are managed in their state. 
Document submitted to conclude E.O.12866 Review

469

Finally, the record generated by the public participation process has an inherent value to States, 

the utilities, and the general public in that it can demonstrate explicitly the manner in which 

issues related to the regulation of CCR landfills and surface impoundments were raised and 

resolved in the state. This record would be a value in any later proceedings seeking enforcement 

of the rule. 

Third, once EPA has approved a SWMP that incorporates or goes beyond the minimum 

federal requirements, EPA expects that facilities will operate in compliance with that plan and 

the underlying State regulations. In those circumstances, EPA’s view is that facilities adhering 

to the requirements of a State program that is identical to or more stringent than an approved 

SWMP will meet or exceed the minimum federal criteria. In addition, EPA anticipates that a 

facility that operates in accord with an approved SWMP will be able to beneficially use that fact 

in a citizen suit brought to enforce the federal criteria; EPA believes a court will accord 

substantial weight to the fact that a facility is operating in accord with an EPA-approved SWMP. 

In addition, as noted above, the record generated by the public participation process in 

developing the SWMP has an inherent value to the States, the utilities, and the general public in 

any such litigation. The more specific the record is on the public process regarding how the 

SWMP would incorporate the minimum federal requirements and any state oversight the more 

valuable it would be in any court proceedings to complement EPA’s approval of the SWMP. As

fully explained earlier, EPA approval of a State SWMP does not mean that the state program 

operates “in lieu of” the federal program as EPA does not have the authority to make such a 

determination. 

The process and criteria for approval of SWMPs are set out in 40 CFR Part 256. The Part 

256 regulations state that EPA has six months from submittal of a plan to either approve or 
Document submitted to conclude E.O.12866 Review

470

disapprove it. The regulations further state that EPA will approve a plan if the agency

determines that the plan: (a) meets the requirement set out in RCRA Section 4003(a) (1), (2), 

(3), and (5); (b) and contains provisions for revisions. Those requirements of 4003 (a) are: the 

identification of the responsibilities of State, local, and regional authorities in the implementation 

of the plan and the means for coordinating regional planning and implementation; prohibition on 

the establishment of new open dumps and the requirement that all solid waste be utilized for 

resource recovery or disposed of in landfills meeting the minimum federal criteria; provision of 

the closing or upgrading of all existing open dumps; and no prohibition on negotiating or 

entering into contracts for the supply of solid waste to resource recovery facilities. In this rule, 

EPA has established minimum national criteria for CCR disposal facilities, which effectively 

define when CCR disposal facilities are open dumps. In order for EPA to approve a revised state 

SWMP, it must determine that the State plan provides enforceable regulatory requirements for 

the closing or upgrading of CCR disposal facilities that constitute open dumps. A state SWMP 

can do so through direct incorporation and implementation of the minimum federal criteria 

established by this rule or through incorporation of alternative requirements that are at least as 

protective of public health and the environment.

EPA anticipates that it will be able to review and approve State SWMPs that adopt the 

federal regulations in total or go beyond the federal minimum criteria very quickly; EPA’s 

review of plans that do not adopt the federal minimum criteria or alter them substantially is likely 

to be more difficult and therefore more time consuming. EPA’s review of and decision to 

approve or disapprove a State solid waste management plan will be based on the record before 

the Agency at the time of that decision. This record includes the record developed during the 

public participation process in which the State engaged prior to submitting the revised SWMP to 
Document submitted to conclude E.O.12866 Review

471

EPA for approval. Should information come to EPA’s attention at a later date that a State is not 

implementing its approved plan or taking actions at variance with the plan’s provisions, EPA 

will take appropriate steps including potentially withdrawing approval of the SWMP.

Because SWMPs form a critical part of the implementation of this rule, EPA intends to 

engage the States very soon after promulgation of the minimum criteria to develop a streamlined, 

efficient process for review and approval of these revised plans. EPA also intends to develop 

both guidance for States to use to submit revisions and for EPA to use in its review of the 

revisions. 

In addition, EPA is exploring options for developing and publishing the statutorily 

required inventory of open dumps. Specifically, within one year of the promulgation of federal 

criteria under RCRA section 4004(a), section 4005(b) directs EPA “to assist the States in 

complying” with the directive in section 4003(a)(3) that state SWMPs shall provide for closure 

and upgrading of open dumps (i.e., facilities that do not meet the revised Federal criteria) by 

publishing an inventory of all “open dumps” in the US. 42 U.S.C. §6945(b). Because the 

minimum criteria promulgated today include implementation timelines, it is possible for a 

facility to become an open dump in the future for failure to meet the minimum criteria. Thus, 

EPA anticipates publishing an initial inventory and likely subsequent periodic updates. 

Finally, in addition to benefits just described of a revised SWMP, RCRA Section 4005 

provides an incentive in certain circumstances for States to obtain EPA approval on revised 

SWMPs. Under section 4005, States with approved SWMPs can provide additional time for 

facilities that do not meet the national minimum criteria (i.e., “open dumps”), to come into 

compliance. As noted above, within one year of the promulgation of federal criteria under 

RCRA section 4004(a), section 4005(b) directs EPA “to assist the States in complying” with the 
Document submitted to conclude E.O.12866 Review

472

directive in section 4003(a)(3) that state SWMPs shall provide for closure and upgrading of open 

dumps (i.e., facilities that do not meet the revised Federal criteria) by publishing an inventory of 

all “open dumps” in the US. 42 U.S.C. §6945(b). Facilities on this inventory are eligible to 

obtain a “schedule of compliance” from a State with an approved management plan, provided 

certain additional criteria have been met. Specifically, the facility must demonstrate that it is 

unable to use other “public or private alternatives” to manage its waste in the non-compliant unit. 

In such cases, the state may establish a schedule of remedial measures that includes “an 

enforceable sequence of actions or operations” which must lead to compliance within a 

“reasonable time (not to exceed 5 years from the date of publication of criteria).” 42 U.S.C. 

§6945(a). Such a schedule would shield the facility from any suit brought to enforce the criteria. 

Thus, if a State receives EPA approval on its revised plan, it can offer facilities additional time, 

albeit limited, to come into compliance with the federal requirements. EPA expects, however, 

that few facilities will either be eligible for or need to take advantage of this flexibility. First, as 

a practical matter, only a limited number of facilities or units will fall into the category of open 

dumps within the relevant time frames. As noted, an open dump is defined as a solid waste 

facility that does not meet the federal minimum criteria. 42 U.S.C. §6903(14). As also 

explained, the final criteria establish time frames for facilities to implement the technical 

requirements, ranging between six months to several years, including certain provisions that 

authorize extensions. Until those deadlines pass, the facility is not an open dump and therefore 

would not be eligible for or need a compliance schedule under section 4005. Because the statute 

limits the States’ ability to set compliance schedules to 5 years from the publication of the 

criteria, if a facility is out of compliance with the criteria either shortly before or after this time 

5-year frame, from a purely practical perspective, compliance schedules are no longer a viable 
Document submitted to conclude E.O.12866 Review

473

option. Thus for certain of the provisions (e.g., closure, which generally must be completed 

within five years) compliance schedules would never be available. 

Second, the time frames in the regulation reflect EPA’s considered judgment of the 

amount of time that would realistically be needed under normal circumstances for a facility to 

come into compliance, based on standard engineering practices used throughout the industry. 

Most facilities will, in fact, be able to comply with the federal criteria within the specified time 

frames, and so will not need to seek a compliance schedule. For example, as part of its Dam 

Safety Assessment program, EPA evaluated all CCR surface impoundments with a dam hazard 

potential rating of “high” or “significant,” using criteria that were essentially the same as the 

technical criteria adopted in the final rule. As of the completion of that program, all units were 

either rated satisfactory, or were taking steps to ensure the structural stability of the unit. EPA 

acknowledges that ensuring the structural stability of these units requires continued maintenance 

and oversight, so past compliance is no guarantee of future compliance. However, our 

experience from the Impoundment Assessment Program leads us to expect that the vast majority 

of CCR surface impoundments will be able to demonstrate compliance with the structural 

stability requirements in the final criteria within the specified time frames. Any facility that 

seeks to justify an extension would have a heavy burden to demonstrate that anything longer 

than a minor amount of time is needed to implement the structural stability requirements would 

meet the statutory standard (i.e., be “reasonable”). Similarly, absent factors beyond the facility’s 

control (i.e, “Acts of God”) EPA is unable to envision the circumstances that would support a 

decision that additional time beyond the 30 months already provided in the criteria to comply 

with the ground water monitoring requirements would be “reasonable.” 

Third, RCRA section 4005(a) imposes a number of requirements that will further limit 
Document submitted to conclude E.O.12866 Review

474

both the circumstances in which a compliance schedule may be granted, and the amount of time 

that States will ultimately be authorized to grant. 42 U.S.C. §§ 6945(a). Section 4005(a) 

requires that to obtain a compliance schedule, the facility must first demonstrate that it has 

considered other public or private alternatives to comply with the prohibition on open dumping 

and is unable to utilize such alternatives.126 At a minimum, this means that the facility must 

demonstrate that there are no alternative units that meet the federal requirement, either on-site or 

off-site, that can be used to dispose of the CCR. EPA also interprets this provision to require the 

facility to demonstrate that it has made a good faith effort to comply with the criteria, which 

would include documenting the actions that had been taken, along with the facts demonstrating 

the reasons that compliance was not feasible within the criteria’s time frames. As has been 

previously discussed, cost is not a factor that is appropriately considered under sections 

1008(a)(3), 4004(a), or 4005(a), and so would not provide an adequate justification for these 

purposes either.

Further, the statute requires that a schedule for compliance specify “a schedule of 

remedial measures, and an enforceable sequence of actions, leading to compliance within a 

reasonable time.” Id. This means that any compliance schedule must lay out precisely the 

activities that remain to be completed, along with clear and enforceable deadlines for each. 

Again, this will effectively serve to limit the ultimate amount of time that would be granted in 

any individual case. 

Finally, as stated earlier, the statute requires that any schedule to bring an open dump into 

compliance is to be limited to a “reasonable time,” that is not to exceed five years from the date 

 

126 Upon promulgation of criteria under sections 1008(a)(3) and 4004(a), the continued use of any unit 

that does not comply with these criteria is prohibited, as “open dumping,” unless a compliance schedule 

has been established. 
Document submitted to conclude E.O.12866 Review

475

of publication of the federal criteria. Whether a particular period of time is “reasonable” depends 

on the facts of the particular situation, but, generally speaking, it should take into account the 

technical complexity of the requirement, the activities that remain to be completed, the reasons 

for the lack of compliance, and other particular factors such as geology, geography, weather, and 

engineering circumstances. For example, EPA expects that a significantly lower amount of time 

would be reasonable for a facility that simply chose to delay implementation than for a facility 

whose compliance was complicated by factors beyond its control. Overall, to be consistent with 

the statute, EPA expects that facilities seeking to establish an alternative compliance schedule 

would need to provide a factual justification that not only documents the reasons that compliance 

within the criteria’s time frames was not feasible, but carefully documents the facts that would 

support a determination that any significant extension of time to come into compliance is 

“reasonable.” 

EPA expects that as part of any revised solid waste management plans, a State would 

explain the criteria it intended to use to determine whether and how much additional time to 

comply with the federal criteria should be granted. See 40 C.F.R. §§ 256.04(f) and 256.26. 

Consistent with the statute’s directives, EPA expects that any extension would be limited to the 

time absolutely necessary to bring a unit into compliance, and that five years would not 

automatically be granted. Nor would a revised solid waste management plan that granted all 

“open dumps” an additional 5 years generally meet the regulatory criteria for approval. Id. EPA 

also expects that States would consider the original time frames laid out in the criteria. As 

previously discussed, in developing these time frames EPA sought to achieve a balance between 

the minimum amount of time that would realistically be needed to properly and adequately 

implement the technical requirements, and the need to expeditiously address the significant risks 
Document submitted to conclude E.O.12866 Review

476

associated with CCR units. EPA therefore expects that in granting additional time under 

compliance schedules, States will be guided by the same considerations. As documented 

throughout this preamble, CCR disposal units do pose significant risks to public health and the 

environment; it is therefore critical that actions to implement these criteria be taken expeditiously 

to address these risks. EPA intends to closely review those portions of a State solid waste 

management plan that address the processes and criteria for establishing compliance schedules.

In conclusion, EPA believes that the use of the solid waste management plan revision 

process is the best mechanism available under RCRA subtitle D to address the States’ interest in 

obtaining formal EPA “approval” of their solid waste management plans. EPA will continue to 

work with the States as the rules are implemented to ensure that this process is streamlined and 

efficient.

X. Risk Assessment

EPA revised and updated the 2010 draft risk assessment using mathematical models to 

determine the rate at which chemical constituents may be released from different waste 

management units (WMUs), to predict the fate and transport of these constituents through the 

environment, and to estimate the resulting risks to human and ecological receptors. Modeling 

was conducted in a step-wise fashion, with more refined analyses used at each subsequent step. 

Below, EPA discusses how the risk assessment was revised and updated in response to the 

various public comments received. The Agency also provides a summary of the analyses 

conducted as part of the risk assessment and the final conclusions drawn from these analyses. For 

further discussion, see the revised risk assessment and response to comments documents 

available in the docket.

A. Response to Public Comments
Document submitted to conclude E.O.12866 Review

477

EPA received numerous, general comments on both the draft risk assessment and 

subsequent NODAs. These comments tended to express general support or disapproval for the 

risk assessment methodology, data, or results. However, these comments did not provide any 

specific technical recommendations or data that could be used to improve the risk assessment. 

EPA appreciates the overwhelming interest of the public regarding the Agency’s risk assessment. 

However, without any substantive critique that could be acted upon, EPA could not alter the risk 

assessment in response to these more general comments. To the extent that any commenter 

mentioned substantive issues regarding a specific aspect of the risk assessment, these comments 

are further addressed in subsequent sections of this preamble. 

1. Comments Related to Fate and Transport Modeling

COMMENT: Commenters wondered how realistic results may be using a risk assessment 

model that assumes current conditions will be maintained for 10,000 years. Specifically, 

commenters were concerned about the assumption that constituent concentrations in the leachate 

remain constant throughout that timeframe. In addition, commenters questioned the assumption 

that well use and climate conditions will remain constant for 10,000 years.

EPA RESPONSE: EPA acknowledges that the 10,000-year ground water modeling time 

horizon required further clarification in the revised risk assessment. Thus, the text in the revised 

risk assessment has been updated to make it clear that the selection of a maximum 10,000-year 

time horizon does not mean that all model simulations continue for the full 10,000 years. 

Specifically, Section 4 states: 

EPA ran the model until either the observed ground water concentration of a constituent 

at the receptor point reached a peak and then fell below a model-specified minimum 

concentration (10-16 mg/L), or the model had been run for a time period of 10,000 years.
Document submitted to conclude E.O.12866 Review

478

Although ground water concentrations are modeled beyond the observed peak or 

maximum average concentrations, these post-peak or post-maximum average predictions are not 

used in estimates of risk. In many cases the leachate plume reaches the receptor point much 

sooner than 10,000 years. As discussed in Section 5 and Appendix K of the revised risk 

assessment, on a national scale, both unlined and clay-lined surface impoundments consistently 

pose peak risks within 100 years. Meanwhile, composite liners show much longer peak arrival 

times, close to 10,000 years for most surface impoundment runs. Peak arrival times are longer 

for landfills, and more than 10,000 years for composite-lined landfills. Under such timeframes, 

EPA acknowledges that surface conditions may change significantly, compounding the 

uncertainty associated with the predicted exposures and risks. However, EPA also notes that the 

time to first exceedance of selected risk criteria is typically considerably less than the time to the 

greatest exceedance. 

EPA acknowledges that future ground water use patterns may shift as the number and 

location of receptors changes, and that it is unknown whether future changes in receptor 

locations and other surface conditions would result in greater, lesser, or the same risk as 

predicted in this analysis. However, no known data exist that would allow EPA to do more than 

speculate about future population dynamics. Thus, the Agency relied on the best available data 

on the current population to conduct the revised risk assessment. The approach used to place 

residential ground water wells is further discussed in Section 4 and Appendix B of the revised 

risk assessment, and the associated uncertainties are discussed in Section 5.

COMMENT: Comments related to the specifics of the ground water transport modeling 

were received from commenters. Issues covered in their comments included the following: 

Geochemical Modeling:
Document submitted to conclude E.O.12866 Review

479

 The way that soil and aquifer Kd values were determined and used, including the fact that 

the risk assessment did not explicitly model oxidation/reduction reactions and 

precipitation-dissolution processes that may influence the chemical fate and transport.

 Whether hydrogeologic settings were assigned correctly. 

Selection of Sorbents:

 The selection of iron oxides, and dissolved (DOM) and particulate organic matter (POM) 

to represent all sorbents in soil and aquifer materials.

 The selection of goethite as the iron oxide mineral to use to estimate sorption to vadose 

zone and aquifer materials.

 The treatment of POM and DOM in the MINTEQA2 modeling used to generate the Kd

values (sorption isotherms) used in the analysis.

 The adequacy of sensitivity and uncertainty analyses for the MINTEQA2 modeling.

Kd Values:

 The approach used to determine the value of pH in the aquifer for selecting Kd.

 The subsequent calculation of the retardation factor.

Arsenic Speciation:

 The assumption that arsenic III is the only or dominant form of arsenic is too 

conservative, as arsenic III readily converts to the less mobile arsenic V species under 

aerobic conditions. 

 A commenter requested time to exceedance results for arsenic species and other 

constituents, as well as distance versus concentration output from EPACMTP. 

EPACMTP Assumptions and Simplifications:

 The appropriateness of EPACMTP and its various assumptions and simplifications for 
Document submitted to conclude E.O.12866 Review

480

ground water modeling, including:

 Not altering the chemistry of the aquifer receiving leachate.

 Not simulating variable oxidation-reduction potential conditions or multiple chemical 

species during a model run.

 Not evaluating the potential mobilization of non-waste related metals from soils when 

exposed to leachate with potentially different geochemistry compared to ambient 

conditions.

 Not considering the potential occupation of adsorption sites by naturally occurring metals 

or competition from multiple contaminants.

 Not considering mounding-induced reduction of the unsaturated zone thickness or other 

cases where the ground water table is in direct contact with the bottom of the WMU. 

 Not considering fractured rock, karst, and other complex hydrogeologic settings.

The comments also addressed the general need for more transparency in the data and 

methods used in the analysis and the need for validation and/or comparison of model inputs and 

results to site-specific field data.

EPA RESPONSE:

Geochemical Modeling: 

EPA recognizes that explicit reactive/geochemical modeling would be more realistic than 

using linear and nonlinear partitioning coefficients. EPA considered the use of the Objects 

Representing Chemical Speciation and Transport (ORCHESTRA) model during revisions to the 

risk assessment because it can account for geochemical interactions, such as aqueous 
Document submitted to conclude E.O.12866 Review

481

complexation, precipitation, surface complexation, and ion exchange.127 However, such 

modeling is not a practical approach for a nationwide analysis because the data collection effort 

necessary to populate such a model on a nationwide, location-based level would be prohibitively 

expensive. Even assuming such data were available to populate ORCHESTRA or a similar 

model, the complexity of the algorithms necessary to account for highly variable geochemical 

and hydrogeologic conditions nationwide and the time required to run such a model would also 

be impractical. Furthermore, the use of Kd as a surrogate for dilution/sorption/ precipitation 

processes is a widely used and accepted method in both the scientific literature and the ground 

water modeling community, provided the values of Kd used are appropriate to account for the 

range of potential attenuation processes.128 Therefore, for a nationwide analysis, the use of Kd is 

a practical and necessary simplification. EPA has added discussion to the risk assessment to 

clarify Kd-related issues raised by the commenters. Appendix H of the revised risk assessment 

displays select percentiles of the Kd values used in the analysis. These values were derived from 

the isotherm sampling performed by EPACMTP and used in the modeling (including effective

Kd values for the unsaturated zone). A listing of all individual Kd values available in the 

MINTEQA2 isotherms used in these analyses would not be practicable. Instead, the full input 

and output files are available to the public in the docket.

Some commenters suggested that EPA should focus on the effect of redox potential in the 

ground water on fate and transport. While this is possible, it would take significant effort to set 

up this type of approach for every inorganic constituent considered in the risk assessment, and it 

 

127

 Meeussen, J.C.L. 2003. ORCHESTRA: An Object-Oriented Framework for Implementing Chemical 

Equilibrium Models. Environmental Science & Technology 37(6):1175–1182.

128

 U.S. EPA. 1999. Understanding Variation In Partition Coefficient, Kd, Values Volume I: The Kd 

Model, Methods of Measurement, and Application of Chemical Reaction Codes. EPA 402-R-99-004A. 

OAR. Washington, DC. August.
Document submitted to conclude E.O.12866 Review

482

was determined not to be necessary. EPA did indirectly account for some of the major effects of 

redox potential when modeling arsenic and other constituents for which speciation is known to 

have a significant impact on mobility. For these constituents, a model run was conducted for 

each species under the assumption that all of the constituent mass was present as that speciation. 

Therefore, EPA did not evaluate redox, and acknowledges this is a source of uncertainty for the 

ground water transport modeling approach. Commenters expressed concern about the 

assumption of a single speciation, noting that it is likely that constituents will be present as some 

combination of the different species. EPA acknowledges that this approach is a simplification of 

real world conditions; however, the Agency believes this approach is useful because it provide 

bounding estimates that can inform the risk assessment. 

Regarding the concern that there were possible errors in hydrogeological assignments, 

these assignments have been updated in the revised risk assessment based on a more robust and 

accurate dataset for waste management units (WMU) and facility locations. These data are 

discussed in Section 3 and Appendix B of the revised risk assessment. Because these 

assignments were based on more complete GIS coverages of soils and aquifers across the U.S., 

they are more consistent and reliable than the previous ones in representing the spatial variability 

in hydrogeologic environments needed by the EPACMTP model. 

Selection of Sorbents: 

In recent years, databases of equilibrium sorption reactions have been compiled in the 

literature for several of the dominant potential sorbents in the environment, including two 
Document submitted to conclude E.O.12866 Review

483

common iron oxide minerals: hydrous ferrous oxides (HFO) and goethite.129,130 Because of the 

availability of these data and their prevalence in the environment, these are the sorbent types 

available for MINTEQ2 modeling used to develop constituent sorption isotherms. Other 

common hydrous oxides that can sorb chemicals include hydrous oxides of aluminum, 

manganese, and silicon (Dzombak and Morel, 1990); however, there were insufficient data on 

these to consider their use. To determine the most appropriate iron oxide sorbent, EPA chose 

goethite as the most appropriate form of hydrous iron oxide for the risk assessment to avoid an 

underestimation of risk. While both goethite and HFO are common forms of iron oxide in soils, 

goethite is a much poorer adsorbent than HFO, thereby leading to relatively greater ground water 

plume concentrations. EPA acknowledges that HFOs are common as well and there is the 

potential for HFOs with greater sorption affinities than goethite to be present at some CCR 

disposal sites. In reaching this conclusion, EPA consulted experts who published on this subject 

(specifically, Dr. David Dzombak, Dr. Samir Mathur and Dr. Jerry Allison), developer of 

MINTEQA2. EPA agrees that this was a necessary assumption.

EPA also recognizes that limiting MINTEQA2 to two types of sorptive materials (iron 

oxide and organic matter [DOM and POM]) is a simplification given the wide range or soil and 

aquifer materials that actually adsorb metals (e.g., clay and other soil minerals). However, given 

that the extensive sorption databases needed to perform MINTEQA2 are available for POM, 

DOM, and goethite, they are the best representation of subsurface sorption processes active in 

soils and aquifer materials. This decision and the actual approaches used to model DOM, POM, 

 

129

 Dzombak, D.A and F.M.M. Morel. 1990. . Wiley-Interscience, New York, 393 pp

130

 Mathur, Samir S. 1995. Development of a Database for Ion Sorption on Goethite using 

Surface Complexation Modeling. Carnegie Mellon University, M.S. Thesis, Department of Civil and 

Environmental Engineering.
Document submitted to conclude E.O.12866 Review

484

and goethite are described in detail in MINTEQA2 background documents and the associated 

Response to Peer Review Comments for those documents. 

Finally, with respect to the adequacy of sensitivity and uncertainty analyses for 

MINTEQA2, EPA notes that the 2009 sensitivity analysis showed that only results for strongly 

sorbing constituents were sensitive to the Kd values output from MINTEQA2. In contrast, the 

three risk drivers identified in the revised risk assessment (arsenic, lithium, and molybdenum) all 

tend to be weakly sorbing, with the exception of arsenic in the pentavalent state. Furthermore, to 

the extent Kd affects the risks, Section 5 of the revised risk assessment evaluated these effects by 

examining alternate speciation (e.g., trivalent and pentavalent arsenic) as well as the effect of 

waste type and waste pH. For these reasons, EPA finds that sufficient sensitivity and uncertainty 

analyses were conducted.

Kd Values: 

The approach adopted in the risk assessment to determine the value of pH in the aquifer 

(used to select Kd) and the subsequent calculation of the retardation factor assumed that, after 

entering the aquifer, the leachate plume would thoroughly mix with the ambient, uncontaminated 

ground water. One commenter stated that the mixing zone would only be present at the periphery 

of the ground water plume. This is consistent with the general conceptual model used in this risk 

assessment of uniform subsurface flow with recharge. However, EPACMTP requires a constant 

ground water pH in each model run to model transport with nonlinear sorption isotherms. EPA 

assumed full mixing as a more conservative approach to selecting pH because, for most metals, 

sorption/precipitation tends to increase (i.e., Kd goes up) with higher pH, which is characteristic 

of much CCR leachate (i.e., assuming full mixing lowers the ground water pH and, thus, 

decreases sorption). To characterize the potential effect of this simplifying assumption on 
Document submitted to conclude E.O.12866 Review

485

calculated risk results, EPA conducted an uncertainty analysis that is presented in Section 5 of 

the revised risk assessment.

EPA considered comparing the modeled Kd values to available estimates in the published 

literature, but did not do so for three reasons. First, there are many individual values within each 

Kd isotherm that depend both on constituent concentrations and MINTEQA2 master variables, 

such as pH, organic carbon, and iron oxide concentrations. Second, measured values are limited 

to specific sites where conditions that may not be fully documented, and because such variables 

can vary from site to site, it can be very difficult to determine exactly how well the collected 

values represent conditions across the country. Third, field and laboratory methods for measuring 

Kd vary greatly and are not easy to compare, adding a significant measurement uncertainty to the 

variability issues mentioned above. Therefore, not only would this comparison be complicated to 

perform, it would also be subject to its own numerous uncertainties and unknown biases, making 

it unlikely to provide a basis for definitive conclusions about the representativeness of the current 

approach.

With respect to comments on the calculation of the retardation factor, EPA points 

commenters to U.S. EPA (2003)131 which discusses how EPA uses Kd values to model sorption 

in the subsurface environment.

Arsenic Speciation: 

Commenters also pointed out that literature on arsenic V often shows that it is orders of 

magnitude less soluble than arsenic III, which appears inconsistent with the results of the 2010 

Draft Risk Assessment. The draft assessment found similar exposure concentrations for both 

 

131 U.S. EPA (Environmental Protection Agency). 2003. EPA’s Composite Model for Leachate Migration 

with Transformation Products (EPACMTP). Technical Background Document. , EPA53-R-03-002. 

Office of Solid Waste, Washington, DC.
Document submitted to conclude E.O.12866 Review

486

arsenic species. As a result of a combination of different updates to the revised risk assessment, 

the modeled concentrations of arsenic III and V are now generally an order of magnitude 

different, although the specific results vary between pathways. One cause of this difference is 

likely the increased distances to receptors in the revised risk assessment. The increased distance 

would lead to additional arsenic V attenuation because this species sorbs more readily (i.e., has 

greater Kd values) than arsenic III. Section 5 of the revised risk assessment discusses the 

uncertainty associated with modeling both species of arsenic. For the specific concentrations at 

various distances, EPA directs the commenter to review the input and output files available in the 

docket.

EPA did not model the time to first exceedance of risk criteria, but did conduct a 

sensitivity analysis for the time to peak ground water concentration. The time to peak results for 

arsenic species and other select other constituents are presented in Section 5 of the revised risk 

assessment. The distance to nearest well receptors is also discussed in Section 5 of the revised 

risk assessment. The relation of distance versus concentration was not explicitly evaluated on a 

per simulation basis, rather all receptor well locations within one mile from the WMU footprint 

were included in the analysis to provide a conservative risk estimate.

EPACMTP Assumptions and Simplifications: 

Comments on the treatment of dispersivity within EPACMTP highlighted the need for 

greater transparency about the model’s underlying assumptions and input data sources. The 

documentation for the 2010 Draft Risk Assessment did not include comprehensive tables 

detailing model input parameters, their values or distributional characteristics, and the sources of 

the data used. These values are, in many cases, publicly available in the EPACMTP Background 
Document submitted to conclude E.O.12866 Review

487

and Parameters/Data Background documents.132,133 EPA still finds it inappropriate to duplicate 

this large amount of data. Instead, the revised risk assessment includes an increase in the number 

of references to these documents, and directs readers to refer to these documents for further 

information. Additionally, the full input and output files are available to the public in the docket.

With respect to the fundamental questions raised about the assumptions and 

simplifications built into EPACMTP, EPA acknowledges some limitations within the model. 

Some simplifications are necessary to complete a large, national scale risk assessment, and the 

model provides the most appropriate available tool to complete this type of analysis. As 

discussed in Section 5 of the revised risk assessment, EPACMTP has been thoroughly peer 

reviewed and tested for application in large-scale risk assessments. This section also provides 

additional documentation on these internal and external reviews of the model, its limitations, and 

the associated uncertainties. With respect to particular criticisms levied:

 EPA alters the chemistry of the aquifer receiving leachate by changing the aquifer pH in 

response to full mixing. Alternatively, EPA conducts an analysis in Section 5 using the 

alternate assumption of partial mixing;

 EPA evaluates alternative species in separate model runs. As described in the revised risk 

assessment, EPA believes that presentation of these two results bound the range of 

possible risks from a constituent. To the extent that EPA does not model oxidationreduction potential, EPA notes that this would require geochemical modeling, which was 

not feasible for the reasons discussed above;

 

132

 U.S. EPA. 2003. EPA’s Composite Model for Leachate Migration with Transformation Products 

(EPACMTP): Parameters/Data Background Document. EPA 530-R-03-003. Office of Solid Waste, 

Washington, DC. April.

133

 U.S. EPA. 2003. EPACMTP Technical Background Document. Office of Solid Waste, Washington, 

DC.
Document submitted to conclude E.O.12866 Review

488

 Full mixing of the leachate plume did not demonstrate significant potential to affect 

aquifer pH. Thus, since pH is one of the most significant factors affecting constituent 

mobilization EPA does not believe significant constituent from the underlying soils will 

be mobilized in most cases. Instead, it is a site-specific consideration that is not possible 

to include in a nationwide risk assessment.

 A discussion of sorbent competition as a limitation of the analysis is discussed in 

Attachment H-1 of Appendix H in the revised risk assessment.

 EPA did not consider ground water mounding, ground water in contact with the waste 

management unit, fractured rock, karst, and other complex hydrogeologic settings as 

these are site-specific considerations that could not be accommodated in a nationwide 

risk assessment.

COMMENT: Several commenters discuss the use of site-specific analysis to increase 

confidence in the risk assessment results. They expressed concern that the results are difficult to 

evaluate given the significant variability and uncertainty associated with the national scope of the 

analysis, and that validation or calibration of EPACMTP results with actual data is needed, 

including the potential use of damage cases.

EPA RESPONSE: Commenters expressed concern about validation of the EPACMTP 

model with actual field data and some commenters suggested that EPA should use actual 

monitoring data rather than modeling to assess potential risks. EPA recognizes the importance of 

monitoring data in characterizing specific sites. EPA agrees with the commenters that confidence 

in the results of an environmental fate and transport model increase significantly when model 

predictions can be compared favorably with measured field results. However, site-specific 

modeling involves extensive data collection and detailed modeling (representing site-specific 
Document submitted to conclude E.O.12866 Review

489

conditions and processes), which was not possible for this large, national-scale risk assessment. 

Available site-specific data are limited to a relatively small fraction of locations and settings. 

This risk assessment was intended to represent a broad range of potential conditions. 

Consequently, EPA validated the model results with actual field data by comparing the results of 

the national probabilistic, Monte Carlo analysis to proven/potential damage cases from across the 

United States. These damage cases represent real-world instances of contamination from CCR 

WMUs that provide the best available comparison for the results of the risk assessment. This 

comparison is presented in Section 5 of the revised risk assessment. EPA also provided extensive 

EPACMTP validation results relative to theoretical models and field data in Appendix D of the 

EPACMTP technical background document (U.S. EPA, 2003a,b).134

COMMENT: Comments relating to the number of wells contaminated, the realistic risk 

of exposure, well placement within the plume, distance to receptor wells, identification of 

surface water receptors, surface water interception modeling, the appropriateness of receiving 

water reaches (e.g. the nearest surface water body), and other receptor or well-related issues were 

received from public commenters. 

Surface Water Interception Modeling: 

Regarding surface water interception, many comments were supportive of EPA’s 

approach for simulating the interception of ground water by surface water bodies, which has 

been added to the revised risk assessment. However, some commenters indicated that a 

meaningful allocation of the ground water plume between a surface water body and a 

downgradient well receptor can only be determined reliably with assessment of the system at a 

 

134

 U.S. EPA (Environmental Protection Agency). 2003a. EPA’s Composite Model for Leachate 

Migration with Transformation Products (EPACMTP). Technical Background Document. , EPA53-R-03-

002. Office of Solid Waste, Washington, DC.
Document submitted to conclude E.O.12866 Review

490

local scale. 

Commenters also raised questions regarding the specific surface water interception 

methodology, including the base data and algorithms used to calculate stream base flow, net 

ground water flow, and the contaminant mass loss to ground water. Concern was expressed about 

the large range of possible values used for Monte Carlo sampling without calibrating models to 

site specific conditions and the potential to mismatch parameters. Additionally, concerns were 

raised that the assessment assumed transport directly to the nearest water body without reflecting 

complexities that are often present and could lead to longer transport pathways or to pathways to 

water bodies other than the nearest.

Commenters noted that the vicinity of many WMUs is serviced by a municipal water 

supply, and; therefore, there would be no drinking water receptors associated with these WMUs. 

Comments were also received that the one mile distance considered by the transport model is not 

sufficient, because actual receptor wells in many cases are further than one mile from facilities. 

Comments also highlighted the possibility that modeled receptor well concentrations may 

incorrectly represent actual exposures by sampling from a single aquifer depth. Comments on 

dispersivity noted the need for greater transparency in the report.

Placement of Receptor Wells, EPACMTP Well Inputs and Assumptions: 

Comments related to the risk assessment’s use of water well distances from MSWLFs 

and the Agency’s belief that these distances would be protective for CCR WMUs. Additional 

comments focused on the assumption that the wells used in this assessment are contaminated 

(i.e., located within the plume), even if the well location used reflects a deeper well that may be 

screened in an uncontaminated aquifer; the manner in which the assessment handles 

uncontaminated wells, plume characteristics, ground water–surface water interactions, vertical 
Document submitted to conclude E.O.12866 Review

491

contaminant concentration across a screened interval in an aquifer; and the values used for plume 

dispersivity.

EPA RESPONSE:

Surface Water Interception Modeling: 

In cases where receptor wells are located downgradient from a surface water body that 

intersects the ground water table, some or all of the ground water, along with the mass of 

constituents contained therein, is intercepted by the water body before it can reach the well. This 

interception was not modeled in the 2010 Draft Risk Assessment. However, a review of the input 

database for the 2010 Draft Risk Assessment found that such a water body was present in 

approximately two-thirds of the Monte Carlo runs. Furthermore, ignoring the loss of constituent 

mass had the effect of overestimating exposures. Thus, in the revised risk assessment an 

EPACMTP model post-processor was created to account for surface water interception by 

removing constituent mass flowing into the water body from the ground water plume, and 

leaving only the remaining ground water available to migrate to a drinking water receptor. The 

approach used to account for interception is discussed in further detail in Section 4 and Appendix 

J of the revised risk assessment. 

While commenters were generally supportive of the proposed approach, some indicated 

that a meaningful allocation of constituent mass from ground water into a surface water body 

required site-specific data. Concerns were raised about the assumption that transport occurred 

directly to the nearest water body without reflecting complexities that are often present and could 

lead to longer transport pathways or to pathways to water bodies other than the nearest. EPA 

acknowledges that local conditions can make ground water flow conditions complex, and 

detailed, local-scale assessments would be required to describe these conditions accurately. 
Document submitted to conclude E.O.12866 Review

492

While EPA agrees that local-scale conditions must be considered for precise estimation for 

specific systems, it was impractical for EPA to characterize, simulate, and calibrate models for 

the numerous locations across the nation. Discussion of the uncertainties associated with this 

approach has been added to Section 5 of the revised risk assessment.

Several questions about the surface water interception methodology were raised by the 

public. The qBaseflow input parameter was derived from the NHDplus mean recharge parameter 

(MEAN_RCHRG)135 and the size of the water body catchment and reach (see Appendix B of the 

revised risk assessment). The approach assumes that all streams intersect the shallow aquifer and 

that all streams either gain water from the aquifer or do not interact with the aquifer at all (for 

simplicity and conservatism). As the commenter indicates, qNetflow is a key result calculated by 

subtracting the stream baseflow from the average ground water flow upgradient of the stream. 

The qNetflow value becomes the adjusted ground water flow beyond the stream, reflecting 

ground water losses to the stream. One commenter raised a specific question about how the 

methodology handles cases where qNetflow is less than zero, but greater than the average ground 

water flow. This case does not occur with the methodology adopted by EPA, because qNetflow 

is always equal to or less than the average ground water flow (i.e. streams are assumed not to be 

losing). If qNetflow is negative (i.e., a losing stream), all of the ground water is assumed to 

migrate to any wells on the opposite side of the stream.

Model Validation/Calibration: 

Concern was expressed about the large range of possible values used in the probabilistic 

analysis for certain parameters and the potential for this to result in a mismatch of input 

parameters without proper site-specific calibration. EPA notes that the revised risk assessment is 

 

135 Available online at: water.usgs.gov/GIS/metadata/usgswrd/XML/nhd_recharge.xml
Document submitted to conclude E.O.12866 Review

493

not intended to capture the exact risks at each disposal site. Instead, the revised assessment 

combines the best resolution of site-based, regional and national data available to provide an 

estimate of potential risks that may occur from current disposal practices. While the assigned 

data for any given model iteration may not reflect the exact conditions at a real-world site, the 

resulting sum of all model iterations reflect the range of potential conditions near each WMU, 

weighted by prevalence, across the conterminous United States. 

Placement of Receptor Wells, EPACMTP Well Inputs and Assumptions: 

Comments regarding placement of receptor wells in the probabilistic analysis (also 

known as the appropriateness of receiving water reaches) are the result of a fundamental 

misinterpretation regarding the constraints placed on ground water receptor location to be, as 

described in the 2010 Draft Risk Assessment, “within the contaminant plume.” This constraint is 

more fully explained in Section 4.4.3.6 of the EPACMTP technical background document.136 A 

citation referring readers to that document has been placed in Section 4 of the revised risk 

assessment. Because the comment resulted from a misunderstanding, EPA does not believe the 

sensitivity analysis suggested by the commenter is necessary.

Some commenters were concerned that many residents in the vicinity of some WMUs 

may be serviced by a municipal water supply. Because these residents would not be exposed to 

ground water, the risk assessment could overestimate exposures. EPA acknowledges that there 

may be a large percentage of the population that does not rely on ground water as a source of 

potable water; however, the aim of the risk assessment is to estimate the magnitude of potential 

risk to the exposed population. Thus, this does not represent a significant source of uncertainty in 

 

136 U.S. EPA (Environmental Protection Agency). 2003a. EPA’s Composite Model for Leachate 

Migration with Transformation Products (EPACMTP). Technical Background Document. , EPA53-R-03-

002. Office of Solid Waste, Washington, DC.
Document submitted to conclude E.O.12866 Review

494

the risk assessment. 

Comments were also received that the one-mile distance considered by the transport 

model is not sufficient, because actual receptor wells in many cases are further distant than one 

mile from facilities. EPA conducted a sensitivity analysis, discussed in Section 5 of the revised 

risk assessment, which indicates that risks beyond the one-mile distance are appreciably lower 

than risks within one mile. Given that the highly exposed population was adequately captured by 

a one-mile radius, the significant additional effort required to extend the analysis further 

downgradient was unjustified.

With respect to comments related to the placement of wells within deeper aquifers, EPA 

has a policy of addressing uncertainty by erring in favor of the protection of human health and 

environmental quality. Consistent with this practice, wells screened within vulnerable, surficial 

aquifers (i.e., the top 10 meters of the saturated zone) continue to be the primary focus of the 

Agency’s national-scale modeling efforts. Comments also highlighted the possibility that 

modeled receptor well concentrations may incorrectly represent actual exposures by sampling 

from a single aquifer depth. Wells are typically screened across an extended depth, and may 

capture both contaminated and pristine ground water. Due to the constraints of EPACMTP, EPA 

maintained the current approach of modeling exposures at a single depth. A discussion of the 

uncertainties associated with this approach has been added to Section 5 of the revised risk 

assessment.

In response to comments on the use of MSW landfill data to predict the distance to 

private wells, EPA did not use the MSW data in the revised risk assessment. Instead, EPA used 

synthetic population representations of U.S. Census data to place each household and its 

occupants at discrete points across the landscape surrounding CCR WMUs. Synthetic 
Document submitted to conclude E.O.12866 Review

495

populations are realistic representations of households and individual residents and their 

attributes in a given census area, and are based on methods that identify realistic locations within 

each block by using LandScan 90-meter night-time population distributions to place each 

household across the landscape.137 From these households, a distribution of the distances to the 

nearest well was created. This approach is discussed in more detail in Appendix B of the revised 

risk assessment. Some commenters suggested that EPA develop site-specific estimates of actual 

populations around facilities rather than relying on synthetic populations to determine potential 

receptor locations. The synthetic approach provides the maximum spatial resolution possible for 

publically available population data from the U.S. Census. More site-specific estimates would be 

costly, but not necessarily more accurate. 

Some commenters were also concerned that the assessment did not consider direct 

discharges from surface impoundments to surface water. This pathway was outside the scope of 

the assessment, because it is regulated by the NPDES program. However, this pathway was 

evaluated in Environmental Assessment for the Proposed Effluent Limitation Guidelines and 

Standards for the Steam Electric Power Generating Point Source Category,

138 which will be 

revised in support of final effluent limitation guidelines due to be released in September of 2015.

2. Comments Related to Source Modeling

COMMENT: The majority of the public commentary in this subcategory was dominated 

by the assertion that Toxicity Characteristic Leaching Procedure (TCLP), Synthetic Precipitation 

Leaching Procedure (SPLP) and other laboratory leachate test data are not applicable to CCR 

 

137

 Bhaduri, B., E. Bright, P. Coleman, and M. Urban. 2007. LandScan USA: A high resolution geospatial 

and temporal modeling approach for population distribution and dynamics. GeoJournal 69:103–117.

138

 U.S. EPA. 2013. Environmental Assessment for the Proposed Effluent Limitation Guidelines and 

Standards for the Steam Electric Power Generating Point Source Category. EPA-821-R-13-003. Office of 

Water. Washington, DC. 20460. April. 
Document submitted to conclude E.O.12866 Review

496

wastes. Comments specifically regarding the use of Leaching Environmental Assessment 

Framework (LEAF) data for modeling leaching behavior noted that the data should be applied 

appropriately and pointed out the following: (1) that the range of conditions (i.e., range of pH) 

encompassed by the LEAF data is broader than those conditions found in the field for CCR 

disposal; (2) high pH limits the mobility of leaching constituents; (3) the need for validating 

LEAF leachate concentrations against field data if available; and (4) the reliability of the LEAF 

data is questionable as a result of inconsistencies identified in the LeachXS LiteTM database.

EPA RESPONSE: Only pore water and impoundment water data were used to 

characterize surface impoundments. Therefore, the comments received on the use of laboratory 

leachate data are not relevant for the surface impoundment scenario. For landfills, EPA agrees 

that TCLP, SPLP and other single pH test methods may not be the most appropriate leachate 

extraction methods for all waste streams and all disposal scenarios. The 2010 Draft Risk 

Assessment relied on a hierarchy of dissolved concentration data to characterize leaching from 

landfills, ranging in order of preference from field leachate data to TCLP. However, new data 

collected using the LEAF test methods have been made available through a series of EPA 

reports.139,140,141 LEAF were collected with three LEAF methods, specifically: 

 

139 U.S. EPA. 2006. Characterization of Mercury-Enriched Coal Combustion Residues from Electric 

Utilities Using Enhanced Sorbents for Mercury Control. EPA-600/R-06/008. Prepared by F. Sanchez, R. 

Keeney, D. Kosson, and R. DeLapp for the U.S. Environmental Protection Agency, Air Pollution 

Prevention and Control Division. February.

140 U.S. EPA. 2008. Characterization of Coal Combustion Residues from Electric Utilities Using Wet 

Scrubbers for Multi-Pollutant Control. EPA/600/R-08/077. Prepared by F. Sanchez, D. Kosson, R. Keeney, 

R. DeLapp, L.Turner, and P.Kariher for the U.S. Environmental Protection Agency, Air Pollution 

Prevention and Control Division. July.

141 U.S. EPA. 2009. Characterization of Coal Combustion Residues from Electric Utilities – Leaching and 

Characterization Data. EPA-600/R-09/151. Office of Research and Development, National Risk 

Management Research Laboratory, Research Triangle Park, NC. December.
Document submitted to conclude E.O.12866 Review

497

 SW-846 Method 1313 (and its predecessor, Method SR02); 

 SW-846 Method 1314; and 

 SW-846 Method 1316 (and its predecessor, Method SR03).142

With the availability of the LEAF data, EPA no longer relied on other data sources to 

model landfills because the inability to identify trends in leaching behavior from single pH tests 

made it impossible to link these data together with the LEAF data in the probabilistic analysis. 

The LEAF data provide information on the leaching behavior of CCR for a range of pH values 

observed in CCR landfills, as well as the liquid-to-solid ratio of the pore water. The data from 

these three methods were used in conjunction to characterize landfill leaching. While the natural 

pH range for any individual sample may be narrower than the full range analyzed with the LEAF 

methods, many facilities burn a range of coal types under varying operating conditions, and codispose with other materials, so the range of pH for a specific CCR sample may be exposed to is 

wider than the pH estimated based on one sample alone. 

EPA agrees that appropriate use of the data is needed to ensure that data represent likely 

conditions of leaching occurring at range of facilities nationwide taking into account local 

specific environmental conditions, the geometry of monofill, type of coal, air pollution control, 

and other factors that affect leaching. Since the NODAs were released, a report comparing

leachate from field and laboratory analyses has been completed.143 The report includes the use of 

geochemical speciation modeling as needed to reflect site-specific factors affecting leaching, and 

shows that LEAF methods provide realistic predictions of environmental releases across the 

 

142

 Methods SR02 and SR03 are predecessor methods to SW-846 Methods 1313 and 1316.

143 U.S. EPA. 2014. Leaching Test Relationships, Laboratory-to-Field Comparisons and Recommendations 

for Leaching Evaluation using the Leaching Environmental Assessment Framework (LEAF). EPA-600/R14/061. EPA Office of Research and Development, National Risk Management Research Laboratory, 

Research Triangle Park, NC, 27711. November
Document submitted to conclude E.O.12866 Review

498

range of pH.

All three LEAF methods are summarized in Appendix C, with the leachate data provided 

in Attachment C-5 of the revised risk assessment. Additionally, the inter-laboratory validation 

for these methods are described in U.S. EPA (2012a,b)144,145 while Kosson et al. (2002)146

provides the detailed test methodology for the predecessor methods, SR02 and SR03. The noted 

discrepancies and classification errors within LeachXS Lite have been corrected.

COMMENT: Public comments focused on the general relevance of the facility data based 

on age and noted that newer data should be used to more accurately reflect the current state of 

CCR management. Related comments cited that the grouping of waste and liner types by facility 

is not representative of current conditions. Another commenter suggested that the outcomes for 

different liner types were not comparable and should not be used to make relative conclusions 

about liner performance. It was also suggested that the assumed three-foot clay layer underlying 

composite liners is too thick, and two feet would be more representative of current practice. 

Commenters also described existing management controls required in some geographical 

locations that mitigate potential risks (e.g., liners, leachate collection) and requested that EPA 

reflect the existence of those controls in their analysis, as well as mismanagement scenarios 

when these controls are not in place.

 

144

 U.S. EPA. 2012. Interlaboratory Validation of the Leaching Environmental Assessment Framework 

(LEAF) Method 1314 and Method 1315. EPA/600/R-12/624. Prepared by A.C. Garrabrants, D.S. Kosson, 

R. DeLapp, P. Kariher, P.F.A.B. Seignette, H.A. van der Sloot, L. Stefanski, and M. Baldwin for the U.S. 

EPA Office of Research and Development, Air Pollution Control Division. September.

145

 U.S. EPA. 2012. Interlaboratory Validation of the Leaching Environmental Assessment Framework 

(LEAF) Method 1313 and Method 1316. EPA/600/R-12/623. Prepared by A.C. Garrabrants, D.S. Kosson, 

L. Sefanski, R. DeLapp, P.F.A.B. Seignette, H.A. van der Sloot, P. Kariher, and M. Baldwin for the U.S. 

EPA Office of Research and Development, Air Pollution Control Division. September.

146

 Kosson, D.S., H.A. van der Sloot, F. Sanchez and A.C. Garrabrants. 2002. An integrated framework for 

evaluating leaching in waste management and utilization of secondary materials. Environmental 

Engineering Science 19(3):159–204.
Document submitted to conclude E.O.12866 Review

499

EPA RESPONSE: Since the purpose of the risk assessment was to evaluate risks for the 

universe of currently operating facilities and WMUs, EPA generally agrees with the commenter 

that the 1995 EPRI and 2006 DOE survey data relied on in the 2010 Draft Risk Assessment may 

be outdated. Thus, EPA collected data from several new sources of information on the facilities, 

WMUs, and liners that are present at the time of this analysis. Further discussion of these data 

sources is available in Section 2 and Appendix A of the revised risk assessment. 

Regarding the inclusion of mismanagement scenarios, EPA reviewed the high-end pore 

water concentrations and determined that these data represent actual CCR samples and therefore 

represent possible high-end risks from current management practices. To better understand 

which practices may lead to the highest risks, EPA conducted sensitivity analyses that consider 

the influence of liner type, liner design, waste type and other variables on model results. The 

results of these analyses are presented in Section 5 of the revised risk assessment.

Several commenters described existing management controls required in some 

geographical locations that mitigate potential risks (e.g., liners, leachate collection) and 

requested that EPA reflect the existence of those controls in the final risk analysis. The Agency’s 

analysis reflects the presence of different management scenarios at WMUs to the extent the 

available data allowed (e.g., WMUs were assumed to have liners if the information indicated 

such). A key objective of the analysis was to compare the effectiveness of management options 

(e.g., liners; surface impoundments versus landfills) at preventing potential releases and 

exposures. Because the population of WMUs considered in the analysis included a range of 

management controls, the analysis does provide such comparative results between management 

options. The uncertainties associated with the updated facility, WMU and liner data are 

discussed in Section 5 of the revised risk assessment.
Document submitted to conclude E.O.12866 Review

500

COMMENT: One commenter suggested that the risk assessment applied risk results for 

fly ash to bottom ash, FGD sludge, and other CCR wastes, which may result in an incorrect 

estimate of risks for these other wastes. Other commenters called for EPA to evaluate each CCR 

waste independently. A public commenter expressed concern about whether the risk assessment 

adequately considered alternative CCR disposal scenarios. Specifically, it was noted that CCR

codisposed with coal refuse generate more acidic conditions (i.e., lower pH) due to higher-levels 

of sulfide minerals, which may significantly impact the mobility of metals.

EPA RESPONSE: In the revised risk assessment, EPA modeled a combined ash waste 

types for the majority of surface impoundments and all landfills. Although commenters are 

correct that different CCR wastes may behave differently when monofilled, the 2009/2010 EPA 

survey data indicates that the CCR are codiposed in a majority of units. Thus, EPA believes this 

approach appropriately reflects current disposal practices.

With regard to the evaluation of CCR codisposed with coal refuse, EPA notes that the 

pore water data used to characterize surface impoundments were broken out separately for this 

waste type evaluation. These data reflect samples collected in the field and are representative of 

the pH at which these samples are managed. While some ash and coal refuse samples are highly 

acidic, others are more neutral or slightly basic (full pH range of 1.7 to 8.2). The development 

and application of these waste types is discussed in Section 3, Section 4 and Appendix H of the 

revised risk assessment, while the associated uncertainties are discussed in Section 5. For 

landfills, waste pH, which is the major driver of variations in Kd values used to distinguish waste 

types, was known with great accuracy for CCR nationwide because U.S. EPA (2009a)147

 

147

 U.S. EPA. 2009. Characterization of Coal Combustion Residues from Electric Utilities – Leaching and 

Characterization Data. EPA-600/R-09/151. Office of Research and Development, National Risk 

Management Research Laboratory, Research Triangle Park, NC. December.
Document submitted to conclude E.O.12866 Review

501

compiled a full, nationwide distribution of CCR pH. In this distribution, disposal of ash with coal 

refuse is reflected is the acidic tail of the distribution. For the national probabilistic analysis, 

EPA aggregated model runs for ash and coal refuse (surface impoundments) and acidic waste 

(landfills) with other wastes so that risks reflected the prevalence of these disposal practices. 

However, EPA also performed sensitivity analyses to understand the extent that the lower pH of 

co-managed wastes could affect risks, which is discussed in Section 5 of the revised risk 

assessment.

COMMENT: Commenters stated that it is unclear why EPA chose to approximate 

infiltration through composite liner systems based on leak detection system flow rates from 

industrial landfills that use a different construction design than projected for CCR landfills.

EPA RESPONSE: The composite liner leakage rates used for this risk assessment 

correspond to leakage rates developed for the peer-reviewed Industrial Waste Management 

Evaluation Model (IWEM).148 The types of synthetic liners used are likely to be the same, 

regardless of the type of waste present. EPA is unaware of any factors specific to CCR that 

would exacerbate leakage rates, nor did the commenter provide any. Thus, in the absence of any 

information to the contrary, EPA finds these to be the best available data. 

Because there is currently no approach for differentiating between flow from unimpacted 

water released by the consolidation of clay and from contaminated leakage through the liner, 

EPA excluded data on the subset of composite liners constructed with natural clay from the 

distribution of composite liner leakage rates. EPA did consider the potential impact of 

incorporating these additional data into the risk assessment as part of sensitivity analysis, 

 

148

 U.S. EPA. 2002. Industrial Waste Management Evaluation Model (IWEM) Technical Background 

Document. EPA530-R-02-012. Office of Solid Waste, Washington, DC. August.
Document submitted to conclude E.O.12866 Review

502

presented in Section 5 of the revised risk assessment. 

COMMENT: Concerning the treatment of non-detect values in the risk assessment, one 

commenter recognized that the use of one half the detection limit in calculations has become an 

accepted protocol. However, it was suggested that this approach may not be appropriate in all 

cases, and that newer or more straightforward methods can be applied to improve precision and 

minimize biasing of the dataset. Another commenter noted that mercury was excluded from the 

analysis due to the high number of non-detects.

EPA RESPONSE: Additional constituent data measured with lower detection limits have 

been made available to EPA since completion of the 2010 Draft Risk Assessment. However, the 

overall CCR constituent database still contains a large number of non-detect data for some 

constituents. EPA continues to incorporate all available with the use half the reported detection 

limit as the most appropriate method to account for these non-detects. The commenter is correct 

that much of the pre-2010 mercury data has high detection limits and a large proportion of nondetects. In this one instance, EPA relied only on the newer data made available to the Agency 

since the 2010 Risk Assessment, which was collected through newer methods with significantly 

lower detection limits. A more detailed rationale for this approach is provided in Section 3 of the 

revised risk assessment, along with further discussion of the uncertainty in Section 5.

COMMENT: Comments received related to the effect of waste compaction in landfills 

focused on changes to hydrologic properties of waste materials, such as porosity and hydraulic 

conductivity. These changes may result from compaction, consolidation, hydration or 

geochemical changes, and have the potential to result in either an underestimation or 

overestimation of risks.

EPA RESPONSE: EPA acknowledges that the landfill source model does not consider 
Document submitted to conclude E.O.12866 Review

503

the compaction of CCR waste that may occur over time as a result of anthropogenic activities, 

gravity or infiltrating water. However, no data on either the rate or degree to which these 

processes may occur were provided by commenters or identified elsewhere. EPA considered the 

impacts of this uncertainty in Section 5 of the revised risk assessment.

COMMENT: Public comments focused on assumptions relating to the variability of 

unlined landfill design, landfill clay liner materials, and construction of landfill cover materials 

and construction. Specific comments emphasized that the clay liner and cover thickness 

assumptions (three feet) were too conservative and not conservative enough, respectively. 

Commenters also questioned why composite covers and leachate collection systems were not 

considered for clay-lined landfills. Additionally, commenters stated that there was a high degree 

of variability in the material and design and construction for unlined landfills that was not 

accounted for in the HELP modeling. One commenter also pointed out that the assessment may 

overestimate percolation rates from landfills by underestimating the use of engineering controls. 

In addition, a commenter stated that the assessment assumes that States will require liners in all 

cases which may not be the case, thereby weakening the regulation.

EPA RESPONSE: For both unlined and clay-lined landfills, EPA used Hydrologic 

Evaluation of Landfill Performance (HELP) model-derived infiltration rates. These infiltration 

rates assume that the cap placed on top of the landfill at the end of its useful life will remain 

intact for the duration of the risk assessment, up to a maximum 10,000 years of modeling. A 

commenter pointed out that hydraulic conductivity of a clay liner is likely to increase by orders 

of magnitude due to desiccation resulting from natural temperature cycles. Additionally, 

commenters stated that there was a high degree of variability in the material and design and 

construction for unlined landfills that was not accounted for in the HELP modeling. EPA has 
Document submitted to conclude E.O.12866 Review

504

adopted the use of the HELP model, which was subject to both peer and administrative review, 

as the source of unlined and clay-lined infiltration rates for landfill for nearly two decades. EPA 

acknowledges that there are limitations in using HELP. However, the model has been tested and 

verified as discussed in the EPACMTP Parameter/Data Background Document.149 To the extent 

that the performance of the cap will decrease over time, EPA acknowledges that unlined and 

clay-lined infiltration rates calculated by HELP may be underestimated, however the degree of 

that underestimate is unknown. Discussion of this uncertainty has been added to Section 5 of the 

revised risk assessment.

COMMENT: One commenter expressed concern over the fact that the assessment 

modeled all disposal sites above the water table. The commenter indicated that many surface 

impoundments and landfills are deep and can come in direct contact with the water table. This 

will result in an underestimation of peak concentrations, arrival times and risks for these WMUs. 

Furthermore, the commenter emphasized that the use of the unsaturated zone flow module to 

calculate infiltration from the bottom of impoundments underestimates true risks in the 

consolidated sediment, and noted that clogged soil layers should be treated as saturated rather 

than unsaturated.

EPA RESPONSE: EPA acknowledges that EPACMTP is not designed to handle 

scenarios where the water table is above the bottom of the landfill. However, EPACMTP can 

accommodate surface impoundments in direct contact with the water table. If unit geometry and 

the selected depth to the water table create a scenario where the bottom of the unit is in contact 

with the water table, then the entire soil column is considered saturated. Otherwise, even for very 

 

149

 U.S. EPA. 2003. EPA’s Composite Model for Leachate Migration with Transformation Products 

(EPACMTP): Parameters/Data Background Document. EPA 530-R-03-003. Office of Solid Waste, 

Washington, DC. April.
Document submitted to conclude E.O.12866 Review

505

high infiltration rates, regions beneath impoundments will remain partially saturated when there 

is sufficient distance between the unit and the water table. EPA has added a discussion of the 

uncertainties associated with WMU source terms and EPACMTP in Section 5 of the revised risk 

assessment.

EPA believes the commenter misunderstood how the sediments were modeled for surface 

impoundments. The EPACMTP unsaturated zone module assumes that the 0.2 m of consolidated 

sediments at the bottom of a surface impoundment are always saturated whereas the 0.5 m of 

clogged native soil are assumed to be unsaturated when the bottom of the surface impoundment 

is above the water table.

COMMENT: Public commenters recommended that EPA address the future increase in 

mercury and NOx compounds levels in CCR that will result from mercury capture from flue gas 

under new emission control regulations. Commentary pointed out that the recent Vanderbilt 

study should provide data that could be used to expand the risk assessment in this area.

EPA RESPONSE: The risk assessment was designed to evaluate the risks associated with 

current management practices and, as such, draws no conclusions about the potential for future 

air pollution technologies to alter the composition or leaching behavior of CCR wastes. 

However, it has been shown that newer mercury pollution control technologies currently in place 
Document submitted to conclude E.O.12866 Review

506

have the potential to affect leaching behavior.150,151,152 Thus, EPA conducted a sensitivity analysis 

to evaluate the risks associated with existing units that dispose of this waste; however the data 

were too few to allow EPA to draw conclusions about the effect of pollution control technologies 

on the risks. This sensitivity analysis is presented in Section 5 of the revised risk assessment.

COMMENT: Multiple public commenters noted that additional pore water will improve 

the risk assessment, but TCLP and SPLP data are not appropriate for use as source 

concentrations. Additionally, commenters stated that EPA applies the LEAF data to pH 

conditions that are not realistic to CCR disposal scenarios. Although LEAF provides a more 

representative and scientifically sound approach, it must be correctly adapted. Alternative 

statistical methods to represent the input data as a range is certainly feasible and could enhance

the risk assessment if the range of data is used as an input to the risk assessment.

Commenters agree that the LEAF data does provide useful information, but point out that 

it is associated with the potential for leaching and does not represent actual leaching of a specific 

CCR under actual field conditions. Commenters argues that field leaching data should not be 

mixed with laboratory data, and that EPA's field leachate dataset (for landfills and 

impoundments) is not adequate for use in the CCR risk assessment. Specific efforts 

recommended to properly utilize the LEAF data include: Use of probability density functions for 

 

150

 U.S. EPA. 2006. Characterization of Mercury-Enriched Coal Combustion Residues from Electric 

Utilities Using Enhanced Sorbents for Mercury Control. EPA-600/R-06/008. Prepared by F. Sanchez, R. 

Keeney, D. Kosson, and R. DeLapp for the U.S. Environmental Protection Agency, Air Pollution 

Prevention and Control Division. February.

151

 U.S. EPA. 2008. Characterization of Coal Combustion Residues from Electric Utilities Using Wet 

Scrubbers for Multi-Pollutant Control. EPA/600/R-08/077. Prepared by F. Sanchez, D. Kosson, R. Keeney, 

R. DeLapp, L.Turner, and P.Kariher for the U.S. Environmental Protection Agency, Air Pollution 

Prevention and Control Division. July.

152

 U.S. EPA. 2009. Characterization of Coal Combustion Residues from Electric Utilities – Leaching and

Characterization Data. EPA-600/R-09/151. Office of Research and Development, National Risk 

Management Research Laboratory, Research Triangle Park, NC. December.
Document submitted to conclude E.O.12866 Review

507

leachate concentrations based on pH and/or L/S ratios in the Monte Carlo process; Selection of 

leachate concentrations based on pH and L/S and tied to the geographic location of the WMU 

and CCR type; and geochemical modeling to incorporate reactions once leachate impacts 

groundwater.

A few commenters pointed out that the pore water data are generally representative, 

although concerns were raised about the highest arsenic concentration (81 mg/L) in the dataset. 

One commenter believed that although the addition of new data is an improvement, EPA could 

greatly improve the accuracy of the model’s results by removing the extreme and unsubstantiated 

outlier data driving its high risk cases. Another commenter believed the assumption that 

concentration of contaminants in the sediment pores (applicable to a post closure scenario) 

would be equal to the concentration assigned to in the impoundment water would result in 

underestimated risks. Additionally, commenters noted that EPA should classify the data 

according to CCR type and coal type. 

Overall, commenters support updates to the pore water data and the use of statistical 

method to normalize the data curve. However, one commenter noted that EPA should not use 

commenter-submitted CCR pore water data unless it meets requisite applicable data quality 

requirements. Another commenter stated that EPA needs to provide better clarity on these 

solicited comments (on the use of older pore water data) and provide these documents in the 

docket. Without these documents, the reader does not have a complete understanding of comanaged material containing CCR. Another comment noted that properly collected field pore 

water (freely draining) samples should take priority over any of the laboratory generated data and 

freely draining pore water is more representative of leachate releases than tightly held pore 

water.
Document submitted to conclude E.O.12866 Review

508

EPA RESPONSE: The use of pore water data is still considered the most appropriate 

approach to estimate constituent fluxes to ground water for CCR surface impoundments. This is 

because pore water better represents the leachate seeping from the bottom of the impoundment 

than impoundment water samples. EPA did not use available LEAF data for surface 

impoundments because a national distribution of pH was not available to allow the Agency to 

probabilistically assign LEAF concentrations to these units, and because there was no way to 

account for partitioning of the leachate into wastewater versus porewater. Thus, EPA has 

continued to rely on pore water data, supplemented with data from the 2010 comments. EPA 

appreciates commenter support on the use of pore water data and statistical methods for data 

analysis for surface impoundments. EPA agrees that data available for minefill sites may not be 

representative of disposal in surface impoundments. Thus, these data were not considered in the 

revised risk assessment. The specific handling of pore water concentration data with site 

quartiles, rather than site averages, is discussed in Section 4 and Section 5 of the revised risk 

assessment report. 

EPA agrees that TCLP and SPLP data are less appropriate for CCR disposal scenarios 

and no longer uses these data in the revised risk assessment. EPA adapted the LEAF methods 

and data for landfills, as this is the best available approach and data to represent CCR landfill 

leachates, and does not mix or use field data with LEAF laboratory results for landfill leachate. 

The LEAF data are considered the most robust and technically defensible data available. As 

noted in the 2010 Environmental Science and Technology publication,153 the data represents the 

largest collection of comprehensive characteristic leaching data to date. 

 

153

 Thorneloe, S., D. Kosson, F. Sanchez, A. Garrabrants, and G. Helms. 2010. Evaluating the Fate of 

Metals in Air Pollution Control Residues from Coal-Fired Power Plants. Environ. Sci. Technol. 44:7351-

7356.
Document submitted to conclude E.O.12866 Review

509

A commenter noted that the LEAF data provide the potential for leaching and not actual 

leaching of a specific CCR under actual field conditions. The commenter suggests using 

probability distribution of key factors affecting leaching behavior [i.e., pH and liquid/solid ratio 

(L/S)] and site specific data tied to the geographic location of the management unit and the type 

of CCR being managed. In the revised risk assessment, pH is expressed as a national distribution 

for selecting leachate concentrations developed to represent CCR nationally, and L/S is 

considered in estimating washout leachate concentrations based on field data observations. The 

use of the pH distribution developed in U.S. EPA (2009)154 does capture the range of potential 

variability in pH conditions at CCR sites nationwide and is the best approach possible given the 

current availability of information on site-specific coal ash chemistry. Although leachate 

concentrations were selected considering pH and L/S conditions that are nationally 

representative, EPA does not have the detailed and extensive site-specific measurements that 

would be needed to tie CCR and leachate concentrations to specific WMU locations. Instead, 

EPA adopted a national probabilistic approach that is site-based and representative of risks to 

human and ecological health across the country. The revised risk assessment also provides 

details regarding how the LEAF data are used in combination of geographical specific data such 

as hydrology, precipitation, fill configuration, CCR type, pH, L/S ratio, and other factors that 

take the leaching potential as an input to fate and transport models accounting for attenuation and 

dilution. Additionally, an effort was made to collect CCR samples that characterize the range and 

quantity of coal usage in the U.S. along with likely air pollution control configurations. While 

the data is not statistically representative on a site-specific basis, it is adequate to identify trends 

 

154

 U.S. EPA. 2009. Characterization of Coal Combustion Residues from Electric Utilities – Leaching and 

Characterization Data. EPA-600/R-09/151. Office of Research and Development, National Risk 

Management Research Laboratory, Research Triangle Park, NC. December.
Document submitted to conclude E.O.12866 Review

510

in leaching behavior that relate to differences in materials types, APC technology, and coal rank. 

Geochemical speciation modeling was not conducted because the source term as measured and 

interpreted is conservative, provided that oxidizing conditions occur. 

Regarding the number and concentration of pore water samples, EPA reviewed the highend pore water concentrations and determined that these represent actual CCR samples that 

therefore represent possible high-end risks if CCR is inadequately regulated and managed. EPA 

recognizes that more pore water data would potentially improve the representativeness of the 

dataset, but is convinced that the current dataset adequately captures the possible high end risks 

that are of most interest in the rulemaking, including risks from the mismanagement of CCR 

through codisposal with coal refuse. 

The assumption that saturated contaminant concentrations in surface impoundment 

sediments are at equilibrium with the impoundment waters is a conservative assumption that is 

unlikely to significantly underestimate risks. This assumption is further discussed in Section 5 of 

the revised risk assessment report.

Regarding commenter-submitted pore water data, EPA conducted a review of the 

additional datasets provided by the commenters with respect to relevance and data quality. Based 

on the available information, EPA determined that the selected datasets were relevant and 

acceptable in terms of data quality requirements. However, EPA does not have sufficient data to 

distinguish between freely draining and tightly bound pore water data at this time. Overall, EPA 

agrees that the use of these data introduces some uncertainty into the analysis, which is discussed 

in Section 5 of the revised risk assessment.

COMMENT: One commenter questioned the assumption that there will be no net 

addition of waste into a surface impoundment during and after the operational life, noting that 
Document submitted to conclude E.O.12866 Review

511

impoundments are frequently deepened. Additionally, many surface impoundment wastes are left 

in place at the time of closure, so that the waste behaves more as a landfill than a surface 

impoundment (and increasingly, with new landfills being constructed on top of previous surface 

impoundments). Another commenter questioned why the conceptual model assumes that 

impoundments are always full during their operating life, which overestimates releases to the 

subsurface. Additionally, a commenter noted that the assumption of only 0.2 m of sediment 

accumulation underestimates the amount of sedimentation and subsequently overestimates the 

amount of percolation to the subsurface. The commenter stated that in actual operation, ash 

thickness can increase up to 30 feet or more, eventually filling the impoundment, which results 

in a significant decrease in percolation through the base. Furthermore, the commenter questioned 

the assumption that post-closure percolation continues at the same rate as during active 

operations.

EPA RESPONSE: Based on the 2009/2010 EPA surveys, it was assumed that the 

majority of the surface impoundments are storage impoundments, which are continuously 

dredged. Because these facilities have other units (whether onsite or offsite) established for 

disposition, it likely that the majority of waste in the dredged impoundments would be removed 

by the end of the unit’s operating life. Regardless, an uncertainty analysis provided in Appendix 

K demonstrates that the risks during the operating life of surface impoundments are greater 

because the higher hydraulic head drives leachate into underlying soils with greater force than 

gravity alone post-closure. Therefore, EPA did not explicitly model the post-closure phase of 

surface impoundments. The uncertainties resulting from this decision are discussed in Section 5 

of the revised risk assessment. 

EPA acknowledges that EPACMTP is restricted to modeling flow as steady state with the 
Document submitted to conclude E.O.12866 Review

512

assumption that an impoundment always has a fixed depth of wastewater. EPA further 

acknowledges that such an assumption may overestimate infiltration. The surface impoundment 

conceptual model assumes that sediments are periodically dredged and removed and that the 

long-term average thickness of the sediment is approximately 0.4 m, with half of that layer 

consolidated. EPA has used EPACMTP and its predecessor model versions for a longstanding 

time period and it has undergone multiple rounds of internal and external review. The reviews 

associated with EPACMTP and its limitations are further discussed in Section 5 of the revised 

risk assessment report.

COMMENT: Public commenters suggested that risks from operating landfills should be 

considered along with those that occur post-closure. These commenters questioned whether 

greater risks may occur during site operations when wastes are uncovered and exposed directly 

to precipitation. Additional commenters noted that complete leaching of all constituent mass at a 

constant concentration is overly conservative.

EPA RESPONSE: The landfill source model used in this risk assessment is not able to 

address landfills during operation because the non-linear sorption isotherms used require a 

constant, annualized infiltration rate throughout the duration of leaching. Instead, the revised risk 

assessment assumed that the full footprint of the landfill is filled to capacity with a cap no less 

permeable than the soil or liner underlying the WMU is present at the start of leaching. EPA 

acknowledges that this approach introduces some uncertainty into the analysis, the potential 

impacts of which are discussed in Section 5 of the revised risk assessment.

With respect to comments that complete leaching of all constituent mass is overly 

conservative, EPA now models landfills using leachable mass as discussed in Section 4 and 

Appendix C of the revised risk assessment. Alternatively, EPA presents a sensitivity analysis of 
Document submitted to conclude E.O.12866 Review

513

these results compared with the results generated using total mass in Section 5.

3. Comments Related to Exposure Scenarios

COMMENT: The commenter emphasized that the risk assessment does not consider 

direct discharges to ground and surface water systems other than ground water infiltration (e.g., 

direct injection to ground water, point and nonpoint discharges to surface water systems). It was 

recommended that EPA consider combining contributions from these sources with CCR ground 

water leaching impacts to calculate the full load of CCR constituents to ground water and surface 

water systems. The commenter continues by suggesting that the use of liners in impoundments 

does not reduce overall hazards if direct discharges are considered in the risk assessment.

EPA RESPONSE: Resource Conservation and Recovery Act (RCRA) waste disposal risk 

assessments do not address direct discharges from impoundments to surface waters because they 

are regulated as permitted point source discharges under the Clean Water Act by EPA’s Office of 

Water. Since this pathway is outside the scope of the risk assessment, the revised risk assessment 

does not consider these releases. However, this pathway was evaluated in the Environmental 

Assessment for the Proposed Effluent Limitation Guidelines and Standards for the Steam

Electric Power Generating Point Source Category,155 which will be revised in support of final 

effluent limitation guidelines (ELG) due to be released in September of 2015. The revised risk 

assessment was updated to note this fact.

EPA is not aware of any CCR disposal where waste is directly injected into ground water 

aquifers, and absent any data on this practice declines to evaluate it.

COMMENT: Public comments were received on the methodology applied to evaluate 

 

155

 U.S. EPA. 2013. Environmental Assessment for the Proposed Effluent Limitation Guidelines and 

Standards for the Steam Electric Power Generating Point Source Category. EPA-821-R-13-003. Office of 

Water. Washington, DC. 20460. April.
Document submitted to conclude E.O.12866 Review

514

exposure to fugitive dust during landfill operations (before closure). The majority of these 

comments focused on the fugitive analysis as presented in Inhalation of Fugitive Dust: A 

Screening Assessment of the Risks Posed by Coal Combustion Waste Landfills,

156 and EPA’s 

proposed approach for refining the analysis. Comments received on the initial fugitive dust 

analysis methodology and modeling ranged from emphasizing that the approach was overly 

conservative in some cases to underestimating risk in other cases. 

Multiple comments were provided on the proposed methodology for refining the fugitive 

dust analysis that was applied in the revised risk assessment. One commenter recommended that 

2010/2011 EPA survey data should be used to refine the fugitive dust analysis for landfills. 

Specifically, the current OW data indicate that active portions of the landfills are significantly 

smaller than the landfills identified in the 1995 EPRI survey. Several comments were received 

that pointed out that the application of AERSCREEN and AERMOD is appropriate if 

representative or realistic inputs are used including meteorological data, material silt content, 

source areas for subcells of ash management units and consideration of common operating and 

control practices, which are in some cases defined by the states (e.g., Virginia). However, one 

commenter expressed concern that no previous or current EPA regulatory model, including 

SCREEN3, AERSCREEN or AERMOD, has been rigorously tested and evaluated for 

performance in modeling fugitive emissions associated with CCR landfills. 

In general, the commenters supported or recommended the use of appropriate AP-42 

factors and other techniques to estimate emissions. Others noted that consideration of deposition 

impacts and constituent-specific modeling is appropriate. One commenter recommended that 

 

156 U.S. EPA. 2010. Inhalation of Fugitive Dust: A Screening Assessment of the Risks 

Posed by Coal Combustion Waste Landfills. OSWER. Washington, DC. September.
Document submitted to conclude E.O.12866 Review

515

EPA should conduct a full-scale assessment that considers fugitive dust as well as emissions 

from landfills and emissions of diesel particulate matter from haul trucks, on-site heavy-duty 

landfill equipment, and diesel-powered pumps and generators, with potential receptors of interest 

as residents and sensitive subpopulations living near the power plant, along the transportation 

route and at the landfill. Another commenter expressed concern over the lack of metal speciation 

data, while another comment concerned gas emissions from the landfills (e.g., hydrogen sulfide). 

One final commenter voiced concern that insufficient information was provided on the modeling 

approach and the model inputs to support evaluation and allow comments on the overall validity 

or propriety of the suggested modeling.

EPA RESPONSE: The majority of the comments received concerning exposures during 

landfill operation (before closure) focused on the assessment of fugitive dust. EPA acknowledges 

that the 2010 Draft Risk Assessment did not evaluate the inhalation pathway, relying instead on 

the findings of a previous evaluation, Inhalation of Fugitive Dust: A Screening Assessment of the 

Risks Posed by Coal Combustion Waste Landfills.

157 This previous evaluation only considered 

releases from windblown emissions and the potential to exceed national ambient air quality 

standards (NAAQS) for particulate matter. 

Based on the comments received, EPA updated the screening analysis of fugitive dust. 

EPA agrees that there are potential risks posed by fugitive emissions from sources beyond wind 

and revised the analysis to consider emissions from a range of activities, such as vehicular 

activity, unloading operations and spreading/compacting operations. Emissions from these 

 

157

 U.S. EPA. 2010. Inhalation of Fugitive Dust: A Screening Assessment of the Risks Posed by Coal 

Combustion Waste Landfills. OSWER. Washington, DC. September.
Document submitted to conclude E.O.12866 Review

516

sources were calculated using techniques that have undergone extensive peer-review, including 

AP-42: Compilation of Air Pollutant Emission Factors.

158 Screening level modeling was 

performed with a combination of AERSCREEN and AERMOD to estimate dust dispersion and 

deposition rates. Model inputs were selected to be representative of current landfills, 

environmental settings (e.g., meteorological conditions) and common dust management 

practices. Estimated air concentrations were used to screen acute and chronic health risks from 

inhalation, as well as the potential to exceed NAAQS standards. Furthermore, EPA considered 

exposures that may result from the offsite deposition on and accumulation in downgradient 

media. This was done for all relevant metal species. In contrast, EPA did not evaluate emissions 

of hydrogen sulfide to air as EPA has no data on the extent to which this constituent is present in 

CCR or released into the surrounding environment. Further discussion of this screening analysis 

is presented in Section 3 and Appendix F of the revised risk assessment.

COMMENT: Comments both supported and disagreed with the appropriateness of a 

screening analysis to eliminate pathways from consideration in the full-scale probabilistic 

analysis. One commenter pointed out that the EPA conducted a very conservative, but 

appropriate, screen to identify constituents to include in the full-scale probabilistic analysis. 

Another commenter emphasized that a full scale risk assessment should be conducted that 

assesses exposures concurrently through all pathways (e.g., including surface pathways with 

inhalation exposure) for all chemical constituents. In particular, they emphasized that inhalation 

exposures to human carcinogens, such as hexavalent chromium, as well as non-carcinogens may 

occur through the aboveground pathway. Although disagreed over the use of a screening 

 

158

 U.S. EPA. 1985. Compilation of Air Pollutant Emission Factors. Volume I: Stationary Point and Area 

Sources (Fourth Edition). AP-42. U.S. Environmental Protection Agency, Office of Air and Radiation and 

Office of Air Quality Planning and Standards, Research Triangle Park, NC. September.
Document submitted to conclude E.O.12866 Review

517

approach, both commenters expressed concerns over the use of risk attenuation factors to scale 

screening risks to the full-scale risks for the subset of constituents that did not pass the screen 

and were not evaluated under the full scale assessment. Both commenters believe that this 

approach ignores the unique fate and transport properties of the omitted constituents and that the 

use of a simplistic, attenuation factor is not an appropriate way to estimate risk.

EPA RESPONSE: By first conducting the screening analysis presented in Section 3 of 

the revised risk assessment, EPA was able to focus available resources on the characterization of 

risks for exposure routes and constituents with the greatest potential to pose risks. The screening 

analysis conducted for the revised risk assessment considered all of the potential exposure routes 

identified in the conceptual models for surface impoundments and landfills, which included 

aboveground exposures to ambient air, soil, sediment, produce and animal products. Each 

exposure pathway was evaluated for all constituents (and individual species, as appropriate) for 

which both concentration and toxicity data were available.

The screening analysis was developed to be protective of highly exposed individuals. 

Due to the conservative nature of the screening, the calculated risks represent a protective, but 

unlikely, combination of conditions that most likely reflect an upper bound on potential 

exposures for each individual constituent. The revised screening assessment did not rely on risk 

attenuation factors to screen out constituents. All constituents that resulted in screening-level 

risks above human health or ecological criteria, and for which characterization of fate and 

transport could be refined, were carried forward for further consideration in the probabilistic 

analysis, described in Section 4 of the revised risk assessment. It is possible that consideration of 

exposure to multiple constituents through a single pathway or to the same constituent through 

multiple pathways may have resulted in the retention of some additional constituents. However, 
Document submitted to conclude E.O.12866 Review

518

it is highly unlikely that these additional constituents would remain risk drivers once more 

realistic dilution and attenuation in the environment is considered.

COMMENT: Multiple commenters noted that there may be additional constituents 

present in CCR wastes beyond those quantitatively evaluated in the risk assessment. In 

particular, multiple commenters referenced organics and radionuclides. Some commenters called 

on EPA to quantify the risks associated with these additional constituents. Others claimed that 

these constituents are present in low levels and do not pose risk to receptors.

EPA RESPONSE: In the Report to Congress: Wastes from the Combustion of Fossil 

Fuels: Volume 2 - Methods, Findings, and Recommendations,

159 EPA reviewed the available 

data on organic constituents, such as polyaromatic hydrocarbons and dioxins. These data 

indicated that concentrations of all organics are near or below analytical detection limits both in 

CCR and in the leachate released from CCR. Based on the findings of this report, the Agency 

concluded that organic constituents were not risk drivers and did not require further evaluation. 

In the absence of additional data that demonstrate the organic composition of CCR wastes have 

markedly changed, EPA continues to rely on these findings. 

EPA acknowledges that, like other inorganic constituents, naturally-occurring 

radionuclides may be concentrated in CCR waste through the combustion of coal. However, due 

to a lack of data that could be used to characterize leachate concentrations for individual 

radionuclides, a quantitative evaluation of risk was not conducted. To address this data gap, EPA 

has included radionuclides in the list of constituents for ground water monitoring. Furthermore, 

 

159

 U.S. EPA (Environmental Protection Agency). 1999b. Report to Congress: Wastes from the 

Combustion of Fossil Fuels: Volume 2 – Methods, Findings, and Recommendations (EPA 530-R-99-010). 

Office of Solid Waste and Emergency Response. Washington, DC.
Document submitted to conclude E.O.12866 Review

519

potential transport of these constituents downgradient by windblown dust and storm runoff are

addressed through requirements for fugitive dust controls and run-on/run-off controls.

4. Comments Related to Human Exposure and Toxicity

COMMENT: Some commenters argued that EPA underestimated risks by not 

considering combined chemical effects, additive risk and concurrent exposures through multiple 

pathways. One commenter indicated that EPA should conduct a full scale assessment that 

considers concurrent exposure from ingestion of fish and ground water. Commenters also raised 

concerns that some chemical constituents share a common mechanism of toxicity and may affect 

the same body organ or system, resulting in greater risks than predicted through the 

consideration of each constituent separately. 

One commenter noted that the combination of risks from different constituents would not 

change the overall results of the risk assessment. Constituents concentrations found to result in 

an HQ less than 1 in the screening analysis are unlikely to make a meaningful contribution to 

overall risk regardless of whether multiple compounds share the same toxicological endpoints. 

Additionally, the commenter expressed that it would be inappropriate to add the risks from 

different constituents as modeled because the constituents do not all arrive at a hypothetical 

receptor at the same time, due to differing mobility in the subsurface environment.

EPA RESPONSE: EPA acknowledges that this risk assessment considered potential risks 

to human health from individual constituents and individual pathways. EPA acknowledges that 

not explicitly evaluating cumulative risk is a source of uncertainty that may result in some 

underestimation of risks. It is possible that an individual could be exposed to risks from drinking 

contaminated ground water, as well as eating contaminated fish from a local surface water body, 

it is unlikely that these two exposure pathways would occur simultaneously with any appreciable 
Document submitted to conclude E.O.12866 Review

520

frequency in the real world. It is even more unlikely that a receptor would be exposed to both 

media at the high-end concentrations modeled. Therefore, the magnitude of the uncertainty 

introduced into the risk assessment is likely to be small. It is also possible for an individual to be 

exposed to multiple constituents through a single pathway. This is a more likely scenario 

because, as demonstrated by the available data, CCR typically leach multiple inorganic 

constituents. Where exposure to multiple constituents is likely to occur, EPA policy is to assume 

that the risks resulting from these exposures are additive.160 The current probabilistic analysis 

identified individual constituents above risk criteria. Many of the other constituents modeled 

resulted in risks an order of magnitude or more below risk criteria. Thus, the consideration of 

additive risk, even with the high-end risks modeled in this risk assessment, is unlikely alter the 

principal results of the probabilistic analysis. Similarly, because the risks for individual 

constituents were found to be above levels of concern, consideration of additive risk is unlikely 

to meaningfully change the results of the analysis. EPA updated the revised risk assessment to 

include a discussion of the associated uncertainties in Section 5.

COMMENT: Some commenters identified incorrect and inconsistent reporting of toxicity 

benchmark values and recommended conducting a thorough review of literature to ensure the use 

of the most current values were used. One commenter expressed concern over the use of the 

current IRIS value for arsenic carcinogenic effects and believes it underestimates risk. Other 

commenters emphasized that it would be inappropriate for EPA to consider using the draft oral 

cancer slope factor (CSF) for arsenic and the oral CSF for hexavalent chromium [chromium 

(VI)] published by the New Jersey Department of Environmental Protection (NJDEP). 

 

160

 U.S. EPA. 2000. Supplementary Guidance for Conducting Health Risk Assessment of Chemical 

Mixtures. Risk Assessment Forum, Washington, DC. August.
Document submitted to conclude E.O.12866 Review

521

Concerning lead, one commenter supported a peer reviewer’s recommendation to use the 

Integrated Exposure Uptake Biokinetic (IEUBK) model to calculate human health risks, 

especially for young children. Additionally, a commenter requested chemical-specific 

information on toxicity criteria derivation, as well as information on the relationship between 

environmental exposures to specific chemicals and adverse health effects. The commenter 

emphasized that this information would provide an uncertainty discussion regarding toxicity 

values, facilitate communication with the public, and provide a balanced perspective on risk.

EPA RESPONSE: Human health benchmarks were chosen based on the Office of Solid 

Waste and Emergency Response hierarchy (OSWER Directive 9285.7-53).161 EPA reviewed the 

benchmarks to confirm their accuracy and determine whether newer values have become 

available from EPA or other sources used by EPA since the CCR draft risk assessment was 

conducted. The current, updated list of human health benchmarks is provided in Appendix E of 

the revised risk assessment, and the references cited in that appendix provide further information 

on the potential adverse effects and derivation of toxicity criteria. 

For lead, EPA used the drinking water maximum contaminant level (MCL) to estimate 

risks from drinking water exposure in the draft risk assessment. In the revised risk assessment 

EPA continued to rely on the MCL, but also used IEUBK model for lead in children as described 

in Section 5 of the revised risk assessment. While lead failed the screening assessment, risks 

from lead exposure in the probabilistic assessment were well below the risk criterion, and did not 

drive risks in either the probabilistic or any sensitivity analyses.

COMMENT: The commenters questioned why the cancer benchmark of 1×10-5 was 

 

161 U.S. EPA. 2003. Human Health Toxicity Values in Superfund Risk Assessments. Office of Solid Waste 

and Emergency Response Directive 9285.7-53. December.
Document submitted to conclude E.O.12866 Review

522

selected while the typical range used by OSWER and EPA guidance is a range of 1×10-4to 1×10-

6

. The commenters suggested that an explanation is necessary. In particular, one commenter 

requests clarification on the phrase “point of departure” when supporting the use of the cancer 

benchmark of 1×10-5. Concerning noncancer criteria, a commenter suggested that non-cancer 

risks should be report as follows: Worst Case – Assume maximum exposure scenarios including 

exposure 24 hours/day, 365 days/year for 70 years; High End – 95th percentile based on national 

human activity pattern distributions; Central Tendency – 50th percentile (or median) risk based 

on national human activity pattern distributions. Furthermore, another commenter believed that it 

is more appropriate to consider 95th percentiles, rather than 90th percentile, of exposure and risk 

estimates for humans and ecological receptors.

EPA RESPONSE: The rationale for the selected cancer and noncancer risk criteria, based 

on Agency policy, is discussed in Section 2 of the revised risk assessment. A citation to the 

where “point of departure” was originally defined is provided for reference. The rationale for use 

of 90th percentile risk generated by a Monte Carlo simulation is discussed in Section 4 of the 

revised risk assessment.

COMMENT: Commenters questioned the evaluation of only the reasonable maximum 

exposure scenario. Specifically, it was noted that the receptor placement downgradient of an 

unlined management unit does not represent the entire population exposure distribution. One 

commenter suggested that EPA clearly define the exposed population of interest.

EPA RESPONSE: In risk assessments used to develop regulations under RCRA, EPA 

has historically assessed potential risks resulting from a reasonable maximum exposure (RME) 

scenario in order to ensure that the resulting regulation is adequately protective of human health 

without being excessively conservative. The types of data necessary to define the exact 
Document submitted to conclude E.O.12866 Review

523

population that relied on ground water wells as a source of drinking water or consumes fish from 

impacted water bodies are not available. EPA believes that consideration of RME is a reasonable 

and protective alternative, given the available data. Uncertainties associated with the revised risk 

assessment are further discussed in Section 5 of the revised risk assessment.

COMMENT: The commenters questioned the use of data from the 1997 Exposure 

Factors Handbook in the development of intake rate distributions for various exposures, because 

more current data are currently available. Commenters recommended that EPA make updates to 

these parameters using more current sources of information, including the recently released 2011 

Exposure Factors Handbook.162 In addition, some commenters pointed out the potential for the 

available exposure factor data to underestimate or overestimate exposures. One commenter noted 

that the risk assessment did not fully account for the dependence of input variables (e.g., the 

interdependence of body weight and water ingestion rates for children and link between the rate 

of fish consumed from a water body). Another commenter suggested that a sensitivity analysis of 

human health exposure factors be conducted to add to the sensitivity analysis conducted by EPA 

in 2009. 

Regarding fish consumption rates, commenters questioned the representativeness of a 

fixed fish consumption rate drawn from a single study. It was suggested for transparency that the 

risk assessment provide the results of the chi-square tests to demonstrate how well the fish 

consumption rate data fit a log normal distribution. Additionally, it was suggested that fish 

consumption rates should be determined from other studies and more robust data sets. One 

commenter suggested the incorporation of fish consumption rates representative of subsistence 

 

162 U.S. EPA. 2011. Exposure Factors Handbook: 2011 Edition. EPA/600/R-090/052F. National Center 

for Environmental Assessment, Office of Research and Development, Washington, DC. September.
Document submitted to conclude E.O.12866 Review

524

fishers, such as Native American populations that harvest and consume fish as part of their native 

traditions and culture. 

Regarding drinking water ingestion rates, one commenter voiced concern about the 

assumption that ground water is the source of all drinking water. The commenter indicated that 

this is an overly conservative and atypical assumption, as a majority of individuals will consume 

liquids from other sources (e.g., milk, juice, sodas, bottled water, sports and energy drinks).

EPA RESPONSE: This revised risk assessment relied on both the 1997 Exposure Factors 

Handbook (EFH)163 and the 2008 Child-Specific Exposure Factors Handbook (CSEFH)

164 for 

information on human exposure factors for the U.S. population. The 2011 Exposure Factors 

Handbook165 has been completed and updates some of the data from the 1997 EFH. During the 

finalization of this risk assessment, EPA released OSWER Directive 9200.1-120.

166 Although this 

document provides default exposure factors to use for point estimates, EPA is still in the process 

of updating the full distributions necessary for probabilistic analysis. Therefore, this risk 

assessment does not incorporate the data from the 2011 EFH.

Exposure data used for the fish ingestion rates are described in Appendix D of the revised 

risk assessment. Data on site-specific fish consumption rates were not available for use in this 

analysis. Instead, the full distribution of fish consumption rates were drawn from a study of adult 

anglers from Maine that fished from streams, rivers, and ponds. Because age-specific data for 

 

163

 U.S. EPA. 1997. Exposure Factors Handbook, Volume III, Activity Factors. EPA/600/P-95/002Fa. 

Office of Research and Development, Washington, DC. August.

164

 U.S. EPA. 2008. Child-Specific Exposure Factors Handbook. EPA/600/R-06-096F. National Center 

for Environmental Assessment, Cincinnati, OH.

165

 U.S. EPA. 2011. Exposure Factors Handbook: 2011 Edition. EPA/600/R-090/052F. National Center 

for Environmental Assessment, Office of Research and Development, Washington, DC. September

166

 U.S. EPA. 2014. Human Health Evaluation Manual, Supplemental Guidance: Update of Standard 

Default Exposure Factors. OSWER Directive 9200.1-120. February.
Document submitted to conclude E.O.12866 Review

525

children were not available, all child cohorts were assumed to consume fish at the same rate as 

the adult cohort. Data on fish ingestion rates for Native American subsistence fishers are 

currently limited and can vary widely geographically, to the point that the 2011 EFH makes no 

recommendation for representative values. EPA acknowledges that these issues introduce 

uncertainty into the analysis, which are further discussed in Section 5 of the revised risk 

assessment.

COMMENT: Commenters emphasized the need to update exposure factors for childhood 

exposures and recommended that updates include data from the 2011 EFH. One commenter 

stated that the risk assessment appropriately considered the potential fish exposures for children. 

However, they pointed out that the fish consumption rates for children should be lower than 

those applied for adults. Another commenter suggested that the risk assessment should provide a 

clear description of how the exposure duration of child cohorts were used in the risk calculations. 

Specifically, the commenter questioned whether exposure durations were truncated at the end of 

each age cohort or aged through the different cohorts. 

EPA RESPONSE: The revised risk assessment makes use of the 1997 EFH167 and the 

2008 CSEFH168 for information on human exposure factors for the U.S. population. Although, as 

discussed in the preamble sections above, the revised risk assessment does not incorporate data 

from the recent 2011 EFH,169 all child data included in this document was derived from the 2008 

EFH. In addition to child ingestion of drinking water, EPA’s evaluation has been revised to also 

 

167

 U.S. EPA. 1997. Exposure Factors Handbook, Volume III, Activity Factors. EPA/600/P-95/002Fa. 

Office of Research and Development, Washington, DC. August.

168

 U.S. EPA. 2008. Child-Specific Exposure Factors Handbook. EPA/600/R-06-096F. National Center 

for Environmental Assessment, Cincinnati, OH.

169

 U.S. EPA. 2011. Exposure Factors Handbook: 2011 Edition. EPA/600/R-090/052F. National Center 

for Environmental Assessment, Office of Research and Development, Washington, DC. September
Document submitted to conclude E.O.12866 Review

526

account for infant exposures that may occur from formula mixed with contaminated ground 

water. These data are presented in Appendix D of the revised risk assessment. Consistent with 

the commenter’s recommendation for cohort aging, the risk assessment aged receptors through 

each age cohort using age-specific data for exposure factors and physical characteristics that 

were weighted proportionally by the corresponding time period and then summed. Specific 

discussion of truncation values is provided in later in this preamble. 

COMMENT: Public commenters recommended updating BCF values with more current 

references. One commenter questioned why bioconcentration factors were zero for some 

constituents that are essential nutrients (i.e., cobalt and copper). Another commenter voiced

concern that EPA had not fully considered the appropriateness of using BCFs to describe metals 

bioaccumulation, suggesting that current science (including EPA guidance documents) indicates 

that BCFs are poor predictors of tissue metal concentrations due to wide variation in uptake 

patterns governed by several chemical and biological factors. Another commenter recommended 

the use of an approach that would be more robust than the single BCF approach, establishing and 

applying distributions of BCFs. This commenter also recommended that the assessment adhere 

to the EPA policy of using dissolved metals in the calculating the bioconcentration of metals in 

fish, or should provide the rationale for using a different approach.

EPA RESPONSE: EPA recognizes that the use of BCFs may not represent the most 

current approaches available to estimate metal bioaccumulation at individual sites, where fish 

tissue data can be collected. However, as noted by public commenters, BCFs are useful in a 

screening-level assessment and EPA believes they are also appropriate for a national-level risk 

assessment, where site-specific data are not available and collection of site-specific data is not 

viable. 
Document submitted to conclude E.O.12866 Review

527

In some cases, insufficient data to determine a BCF value meant that these constituents 

could not be quantitatively evaluated for this pathway. Regarding the concern expressed with 

respect to zero BCF values, the commenter did not provide alternative BCFs that EPA could 

consider for the constituents at issue. Additionally, EPA agrees that given the latest scientific 

information, distributions of BAFs/BCFs may be better than single BAFs/BCFs because they 

account for changes in bioaccumulation/bioconcentration at different water concentrations. EPA 

is working to develop BAF/BCF distributions for several CCR pollutants of concern but does not 

yet have a robust enough dataset for use for the final CCR Rule. In lieu of this, EPA is 

proceeding with the single BAF/BCF approach for the current analysis. EPA does recognize this 

issue as a limitation for the BCF calculations and considers it as an uncertainty in the risk 

characterization. Overall, EPA agrees that the use of this older data introduces some uncertainty 

into the analysis. These uncertainties are discussed in greater detail in Section 5 of the revised 

risk assessment. 

With the exception of mercury, EPA evaluated bioconcentration based on water column 

concentrations that include contributions from dissolved and solid phases because available 

BCFs represent contributions from both. Because a BAF based only on dissolved-phase 

concentrations was available for mercury, EPA evaluated this constituent using only dissolved 

concentrations. Applying this conservative approach for most constituents ensured protection of 

human health. Even with this conservative assumption, the 90th percentile risks for the 

probabilistic analysis (Section 4) did not exceed risk criteria for the fish ingestion pathway. 

Therefore, this approach is unlikely to have affected the principal findings of the risk assessment.

For the revised risk assessment, EPA reviewed the available literature and identified 

BCFs for additional constituents that previously had no values. As noted in Appendix G of the 
Document submitted to conclude E.O.12866 Review

528

revised risk assessment, the following source hierarchy was used for fish BCFs:

 Primary literature: These are generally papers focused on a single 

chemical170,171,172,173 or may contain data on multiple chemicals.174,175

 U.S. EPA databases/publications: These included ECOTOX176 and the Mercury 

Report to Congress.177

 Other government agency resources: These included ATSDR Toxicological 

Profiles178 and the Hazardous Substances Data Bank.179

EPA also finds that the references provided by commenters provided primarily 

phytotoxicity and accumulation data for terrestrial plants, and were therefore not relevant to 

 

170

 Eisler, R. 1989. Molybdenum Hazards to Fish, Wildlife, and Invertebrates: A Synoptic Review. 

Contaminant Hazard Reviews, Report No. 19, Biological Report 85(1.19). Laurel, MD. August.

171

 Kumada, H., et al. 1973. Acute and chronic toxicity, uptake and retention of cadmium in freshwater 

organisms. Bull. Freshwater Fish. Res. Lab. 22: 157

172

 Lemly AD. 1985. Toxicology of selenium in a freshwater reservoir: implications for environmental 

hazard evaluation and safety. Ecotoxicology and Environmental Safety. 10(3): 314-338.

173

 Murphy, B.R., G.J. Atchison, and A.W. McIntosh. 1978. Cadmium and zinc in muscle of bluegill 

(Lepomis macrochirus) and largemouth bass (Micropterus salmoides) from an industrially contaminated 

lake. Environmental Pollution 17:253–257.

174 Barrows ME, Petrocelli SR, Macek KJ, Carroll JJ. 1980. Bioconcentration and elimination of selected 

water pollutants by bluegill sunfish (Lepomis macrochirus). In: Haque R, ed. Dynamics, exposure and 

hazard assessment of toxic chemicals. Ann Arbor, Michigan, U.S.A.: American Chemical Society. p. 379-

392.

175

 Stephan, C.E. 1993. Derivation of Proposed Human Health and Wildlife Bioaccumulation Factors for 

the Great Lakes Initiative. Draft. Environmental Research Laboratory, Office of Research and 

Development, U.S. Environmental Protection Agency, Duluth, MN. March.

176

 U.S. EPA (Environmental Protection Agency). 2009b. ECOTOX User Guide: ECOTOXicology 

Database System. Version 4.0. Available online at www.epa.gov/ecotox/.

177

 U.S. EPA (Environmental Protection Agency). 1997d. Mercury Study Report to Congress. Volume III 

- Fate and Transport of Mercury in the Environment. EPA 452/R-97/005. Office of Air Quality Planning 

and Standards and Office of Research and Development, Washington, DC.

178

 ATSDR (Agency for Toxic Substances and Disease Registry). 2008. Minimal Risk Levels (MRLs) for 

Hazardous Substances. Available at www.atsdr.cdc.gov/mrls.html.

179

 U.S. NLM (National Library of Medicine). 2011. Hazardous Substances Data Bank (HSDB).

Available online at: toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?HSDB.
Document submitted to conclude E.O.12866 Review

529

EPA’s explicit solicitation on whether the bioconcentration factors drawn from Baes et al. (1984) 

should be considered in the final risk assessment.180

5. Comments Related to Ecological Exposure and Toxicity

COMMENT: Public commenters emphasized the potential importance of cumulative 

ecological risk, whereby an ecological receptor may be exposed to multiple constituents and/or 

pathways concurrently. For example, amphibians may be subject to both dermal and ingestion 

exposure. Public commenters noted that ecological risks were underestimated because the 

following scenarios were not considered for ecological receptors: aboveground pathways, 

contaminant transport to nearby uncontaminated environments, and the inclusion of field data in 

the analysis.

EPA RESPONSE: EPA acknowledges that cumulative effects can be important for 

ecological receptors. However, just as EPA did not consider cumulative human health risks from 

exposures to ground water (discussed in the previous sections of this preamble), they were not 

modeled for ecological receptors. In the national, probabilistic analysis (Section 4 of the revised 

risk assessment), risks for all constituents fell below the ecological criteria. Even the sum of 

modeled risks for all constituents fell below the ecological criteria. In sensitivity analyses 

(Section 5 of the revised risk assessment), which considered different subsets of national disposal 

practices that may drive risks, boron and cadmium were the two constituents found to result in 

risks above ecological criteria. To the extent that cumulative exposures were not evaluated, EPA 

acknowledges that ecological risk could be underestimated to some degree. However, these 

 

180 Baes, C.F., III, R.D. Sharp, A.L. Sjoreen, and R.W. Shor. 1984. A Review and Analysis of Parameters for 

Assessing Transport of Environmentally Released Radionuclides Through Agriculture. ORNL-5786. Oak Ridge 

National Laboratory, Oak Ridge, TN. September.
Document submitted to conclude E.O.12866 Review

530

uncertainties are unlikely to affect the principal findings of the risk assessment. In addition, EPA 

also notes that all surface water risks are orders of magnitude lower than the risks resulting from 

direct discharges modeled in U.S. EPA (2013).181

In contrast to the surface water and sediment exposures, ecological risks for individual 

constituents were appreciably above risk criteria for direct exposure to impoundment wastewater. 

As a result, it is clear that CCR disposal in surface impoundments have the potential to pose risk 

to ecological receptors, even without consideration of cumulative exposures. 

COMMENT: Public commenters stated that the risk assessment does not consider 

sensitive habitats or species. Commenters requested additional consideration of threatened and 

endangered species and the inclusion of ecological field data.

EPA RESPONSE: EPA did not evaluate these sensitive habitats and sensitive/endangered 

ecological receptors because these are inherently site-specific issues for which data on potential 

impacts are often not available and can be difficult to quantify, even on a site-specific basis. EPA 

acknowledges that the inability to quantitatively evaluate the potential for these adverse effects 

represents a source of uncertainty. Discussion of these uncertainties is presented in Section 5 of 

the revised risk assessment. 

COMMENT: Public commenters were concerned that a more conservative approach was 

needed to derive the ecological benchmarks. Multiple commenters also stated that the use of risk 

attenuation factors to scale the screening risks to full-scale risks was inappropriate. Several 

commenters noted that the ecological boron benchmark used for surface water exposures 

contained incorrect units based on an incorrect transcription in the peer-reviewed article. Another 

 

181

 U.S. EPA. 2013. Environmental Assessment for the Proposed Effluent Limitation Guidelines and 

Standards for the Steam Electric Power Generating Point Source Category. EPA-821-R-13-003. Office of 

Water. Washington, DC. 20460. April.
Document submitted to conclude E.O.12866 Review

531

commenter noted that the ecological cadmium benchmark used for direct contact with surface 

water was incorrect.

EPA RESPONSE: Ecological benchmarks were obtained for CCR constituents when 

available and compared with the modeled media concentrations (e.g., surface water, sediment) to 

estimate the HQs used to characterize ecological risk. These benchmarks represent the best 

available estimates of receptor responses based “no effects” (NOAEL) or “lowest effects” 

(LOAEL) study data. In some scenarios, these benchmarks may represent species not actually 

present in the field. In others, these benchmarks may not capture the most sensitive possible 

receptor at every site or for each constituent. While some benchmarks have factors of safety 

included to account for these or other uncertainties, there remains the potential for these 

ecological benchmarks to underestimate risks for the specific species and communities that live 

in surface waters impacted by CCR WMUs. The magnitude of this uncertainty is unknown. 

Consideration of any additional sensitive species not captured by the current benchmarks may 

result in some additional constituents above risk criteria in the probabilistic analysis. EPA notes 

that ecological risks to some of these additional sensitive receptors may be reflected in damage 

cases. However, this site-specific uncertainty is unlikely to affect the national conclusions of the 

risk assessment.

Regarding incorrect benchmark values, an updated boron benchmark was used in the 

revised risk assessment. The units in the fish study from which the previous SCV was derived182

had been erroneously transcribed in Suter and Tsao (1996)183 as μg/L instead of mg/L. The 

 

182 Hamilton, S.J. 1995. Hazard assessment of inorganics to three endangered fish in the Green River, Utah. 

Ecotoxicol Environ Saf 30:134-142.

183

 Suter, G.W., and C.L. Tsao. 1996. Toxicological Benchmarks for Screening Potential Contaminants 

of Concern for Effects on Aquatic Biota: 1996 Revision. U.S. Department of Energy, Oak Ridge National 

Laboratory, Oak Ridge, TN. June.
Document submitted to conclude E.O.12866 Review

532

updated SCV was recalculated using the corrected units. The revised value has been corroborated 

with the authors. Additionally, a continuous criteria concentration (CCC) was used for the 

cadmium surface water benchmark in the revised risk assessment, replacing the previous value. 

The updated values are presented in Appendix E of the revised risk assessment report.

6. Comments Related to the Monte Carlo Analysis Approach

COMMENT: While some public commenters stated that the human health probability 

distributions appeared appropriate, others expressed concern regarding a conservative bias in 

input parameter probability distributions used and the resulting potential for overestimation of 

risks. These commenters noted that the ideal approach would be to estimate the actual risk and 

associated uncertainty rather than weighting the results conservatively.

EPA RESPONSE: The revised risk assessment conducted full-scale probabilistic Monte 

Carlo analysis to quantify human and ecological risks. EPA agrees it would be ideal to produce 

best estimates of actual risk. All input data distributions (e.g., aquifer data, soil type, WMU data, 

climate data, distance to ground water wells, distance to surface water bodies, constituent 

concentrations, water flow data, human exposure factors) were developed in line with this 

objective. However, these distributions were developed from available data and are subject to the 

limitations of these data. In cases where data were not sufficient to fully characterize the input 

distribution, conservative values and assumptions were used to fill data gaps to remain protective 

of human health and the environment. Further discussion of these uncertainties has been added to 

Section 5 of the revised risk assessment. 

COMMENT: Public commenters pointed out that the risk assessment does not formally 

differentiate variability from uncertainty or show confidence limits for risk results, which makes 

it challenging to identify opportunities to reduce uncertainty. One commenter requested that EPA 
Document submitted to conclude E.O.12866 Review

533

discuss the implications of the relatively wide risk distributions, including the reasons why some 

risk distributions are larger than others based on the Monte Carlo results.

EPA RESPONSE: EPA acknowledges it would be ideal to separate variability from 

uncertainty when possible in a probabilistic risk assessment. EPA was able to reduce a 

substantial number of the uncertainties in the revised risk assessment through the acquisition of 

additional data on facilities, environmental parameters, and constituent concentrations. 

Variability and uncertainty are still comingled in a large number of cases due to remaining data 

gaps; however, EPA conducted multiple sensitivity analyses to determine the potential for 

different inputs to affect risk results. Additional discussion of the differences between parameter 

variability, data uncertainty, and model error, as well as discussions of the sensitivity and 

uncertainty analyses, is presented in Section 5 of the revised risk assessment. 

EPA disagrees that there are wide risk distributions. While the commenter correctly 

points to other risk assessments that had closer central tendency and high-end results, those were 

either site-specific assessments or involved no fate or transport modeling. National-scale risk 

assessments will necessarily have wider variability in their results compared to risk assessments 

that are specific to a single site. Thus, the “wider” risk distributions simply reflect the fact that 

different sites with different CCR can have very disparate impacts on human health and the 

environment.

7. Miscellaneous Comments

COMMENT: Some commenters stated that the documentation is incomplete and that an 

independent reviewer could not reproduce the analysis. Another commenter performed an 

independent review and cancer risk estimate and noted that the EPA used a reasonable approach 

for calculating cancer cases in the risk assessment.
Document submitted to conclude E.O.12866 Review

534

EPA RESPONSE: EPA acknowledges that the documentation of the inputs and 

intermediate outputs could have been more transparent for the 2010 Draft Risk Assessment. In 

the revised risk assessment, many of the inputs EPA used are directly discernible from the 

appendices. A summary of the data available in each appendix is presented in Section 1 of the 

revised risk assessment. EPA also acknowledges that the additions and discussions of inputs in 

the document were not sufficient for complete duplication of the results. Thus, the input and 

output files for the draft risk assessment were made available in the docket of the proposed rule 

via an FTP site,184 and final input and output files are being placed in the docket for the final 

rule.

COMMENT: Commenters requested improvement on the graphical presentation of risk 

results. Additionally, commenters requested further explanation of the minimum and maximum 

truncating values, as truncated values may reduce risk estimates. 

EPA RESPONSE: While EPA did not provide a graphical presentation of the risk results, 

this information is more clearly discernible from the full input and output files. For discussion of 

the full inputs and outputs files, see the responses in the preamble section above. With regard to 

truncation, EPA no longer manually truncates input distributions for the human exposure factors. 

Instead, exposure factor distributions in the revised risk assessment were generated with the 

@Risk software (Palisade Co., Newfield, NY),185 as described in Appendix D. EPA has also 

added further discussion of the cohorts to revised risk assessment, with tables comparing each 

cohort’s risk presented in Section 5 of the revised risk assessment.

COMMENT: Commenters requested more complete documentation of the sensitivity 

 

184 Available online at: ftp://ftp.epa.gov/coal-combustion-residues

185 Available online at: www.palisade.com/risk/
Document submitted to conclude E.O.12866 Review

535

analysis. Other comments included a request to add human health exposure factor variables to 

the sensitivity analysis, and to conduct additional sensitivity analyses on different topics (e.g. 

well distance distribution).

EPA RESPONSE: EPA acknowledges the omission of the original sensitivity analysis 

from the docket. EPA updated the sensitivity analysis186 so that it clearly describes the 

methodology that underlies the results summarized in Section 5 of the revised risk assessment. 

This sensitivity analysis was placed in the docket for the proposed rule. 

Human health exposure factor variables were not evaluated in the sensitivity analysis. 

Human exposure factor variables have well-established, peer-reviewed, national distributions 

that are regularly used in probabilistic risk analyses conducted by EPA based on Agency policy. 

Therefore, the contribution of variability in the exposure factors to the variability in risk was not 

particularly useful for understanding the aspects of CCR disposal practices that may drive risk. 

Additional sensitivity analyses such as leachate duration versus leachable content and liner 

performance by thickness were conducted in the revised risk assessment and are summarized in 

Section 5. 

B. Summary of Risk Assessment and Results

1. Problem Formulation

EPA first developed conceptual models to illustrate a general layout of surface 

impoundments and landfills, the chemical constituents that may be released from these WMUs, 

the routes through which these constituents may migrate through environmental media, and the 

types of exposures that may result. These conceptual models were used as the basis for all 

 

186 U.S. EPA. 2009. Sensitivity Analysis for the Coal Combustion Waste Risk Assessment. Draft Technical Report. 

Prepared by RTI International for U.S. EPA, Office of Solid Waste, Washington, DC.
Document submitted to conclude E.O.12866 Review

536

subsequent data collection efforts. EPA first collected data on the coal-fired power plants and 

CCR WMUs located across the United States. EPA then collected regional and national data to 

characterize the environment and receptor population surrounding each WMU. The data 

assembled represent the most current and comprehensive information available to the Agency at 

the time this risk assessment was conducted. Using the data collected, EPA first conducted a 

simplified hazard identification to determine which constituents warranted further evaluation. At 

this stage, EPA considered the presence of a constituent in CCR waste, combined with the 

availability of at least one toxicity benchmark, sufficient evidence of hazard potential. Table 1 

presents a summary of the different chemical constituents retained as constituents of potential 

concern (COPCs) for further analysis. 

Table 1. List of Chemical Constituents Evaluated in the CCR Risk Assessment 

Aluminum Cadmium Iron Molybdenum Strontium

Ammonia Calcium Lanthanum Nickel Sulfate

Antimony Chloride Lead Nitrate / Nitrite Sulfide

Arsenic Chromium Lithium Selenium Thallium

Barium Cobalt Magnesium Silicon Uranium

Beryllium Copper Manganese Silver Vanadium

Boron Fluoride Mercury Sodium Zinc

Risks identified in the subsequent analyses were compared against risk criteria of cancer 

risk greater than 1×10-5 or a noncancer hazard quotient (HQ) greater than 1.EPA typically relies 

on a risk range to determine the point at which regulation is appropriate. EPA uses as an initial 

cancer risk ‘‘level of concern’’ a calculated risk level of 1 × 10-5(one in one hundred thousand) 

or an HQ above 1.0 for any noncarcinogens. For example, waste streams for which the 

calculated high-end individual cancer-risk level is 1 × 10-5or higher generally are considered 

candidates for regulation. Waste streams whose risks are calculated to be 1 × 10-4or higher 

generally will be considered to pose a substantial present or potential hazard to human health and 
Document submitted to conclude E.O.12866 Review

537

the environment and generally will be regulated. Waste streams for which these risks are 

calculated to be 1 × 10-6or lower, and lower than 1.0 HQs or EQs for any noncarcinogens, 

generally will be considered not to pose a substantial present or potential hazard to human health 

and the environment and generally will not regulated. See 59 FR 66075–66077, December 22, 

1994. 

2. Screening Analysis

EPA conducted separate screening analyses for each exposure pathway to identify which 

COPCs are most likely to pose risk to receptors. The results of this screening generally do not 

provide a precise characterization of individual risks that may occur, but rather identify those 

COPCs that are most likely to exceed risk criteria. In cases where well established, postconstruction management practices (“controls”) have been shown to minimize releases from 

WMUs, EPA considered exposures for both an uncontrolled and controlled management 

scenario. 

This screening analysis identified potential risks to human and ecological receptors 

resulting from the releases of particulate matter and the chemical constituents contained therein 

through wind and run-off. Under an uncontrolled management scenario, risks to human receptors 

resulted from the inhalation of windblown particulates in ambient air and the ingestion of soil 

and animal products (i.e., meat and dairy), while risks to ecological receptors resulted from 

exposures to soil and sediment. Under a controlled management scenario, which consisted of 

fugitive dust controls and run-on/run-off controls, all risks associated with these exposure 

pathways decreased to below the criteria. Due to the conservative nature of the screening, there 

is a great deal of uncertainty surrounding the specific risks calculated for these exposure 

pathways. These risks represent a protective, but unlikely, combination of conditions that reflect 
Document submitted to conclude E.O.12866 Review

538

at least an upper bound on potential exposures. Thus, the cumulative effect of these uncertainties 

result in an overestimation of potential nationwide risks to most or all receptors. Therefore, EPA 

makes no direct findings concerning the magnitude of the risks that may occur under either an 

uncontrolled or controlled management scenario, but concludes with a high degree of confidence 

that the reductions achievable with standard management practices are sufficient to be protective 

even under this conservative screening assessment. Based on these lines of evidence, EPA 

concluded that no further characterization was warranted for these exposure pathways. 

These screening analyses identified potential risks to human and ecological receptors 

from leaching of chemical constituents from CCR waste into surrounding environmental media. 

Risks to human health resulted from ingestion of ground water and fish, while risks to ecological 

receptors resulted from exposure to surface water. There was no simple method to estimate the 

effect controls may have for these pathways. However, considerable dilution and attenuation 

may occur before COPCs reach downgradient private wells and surface water bodies. Therefore, 

EPA retained all of the COPCs found to be above risk criteria in ground water and surface water 

for further characterization. In addition, EPA used the uncontrolled screening results for the 

above ground sediment pathway as a conservative proxy for the ground water to surface water 

sediment pathway. As a result, sediment exposures of four COPCs were retained for further 

characterization. Table 2 presents a summary of the chemical constituents retained as COPCs for 

each pathway.

Table 2. List of Chemical Constituents Retained for Probabilistic Analysis

Human Health Ecological

Ingestion of

Ground Water

Ingestion of

Fish

Surface Water

Exposure

Sediment

Exposure

Antimony Arsenic Aluminum Copper Antimony

Arsenic Cadmium Arsenic Iron Arsenic

Boron Mercury Barium Lead Silver
Document submitted to conclude E.O.12866 Review

539

Cadmium Selenium Beryllium Molybdenum Vanadium

Cobalt Thallium Boron Nickel

Fluoride Cadmium Selenium

Lead Chloride Silver

Lithium Chromium Vanadium

Molybdenum Cobalt Zinc

Thallium

These screening analyses also identified potential risks to ecological receptors from direct 

exposure to impoundment wastewater. Unlike the other exposure pathways, no dilution or 

attenuation will occur within impoundment wastewater prior to ecological exposures. Thus, the 

direct exposures considered in the screening analysis provide a reasonable, order-of-magnitude 

estimate of potential risks. Based on the screening analyses, EPA concluded that HQs for 

ecological receptors exceeded 1 from the following constituents (listed from highest to lowest 

potential): arsenic (100), barium (50), aluminum (30), boron (30), selenium (20), cadmium (10), 

vanadium (10), beryllium (2), chloride (2) and chromium (2). Because the screening analysis 

provides sufficient characterization of these exposures, this pathway was not carried forward for 

further analysis.

3. Probabilistic Analysis

EPA conducted a national-scale, probabilistic analysis to better characterize the potential 

risks to human and ecological receptors associated with leachate released from surface 

impoundments and landfills. The specific exposure routes evaluated for these releases were 

human ingestion of ground water used as a source of drinking water and fish caught from 

freshwater lakes or streams, as well as ecological contact with and ingestion of surface water and 

sediment. A combination of models was used to predict COPC fate and transport through the 

environment, receptor exposures, and the resulting risks. Site-specific data were used, 
Document submitted to conclude E.O.12866 Review

540

supplemented by regional and national data sets, to capture the national variability of disposal 

practices, environmental conditions and receptor behavior. EPA modeled risks for both highly 

exposed individuals (90th percentile risks) and more moderately exposed individuals (50th 

percentile risks). In instances where the speciation of a COPC has been shown to greatly affect 

fate and transport, EPA modeled multiple species to provide a bounding on potential exposures.

Table 3 shows the 90th percentile human health risks to the most sensitive age cohorts 

for constituents that exceeded the risk criteria. Risks are presented for arsenic modeled entirely 

as two different species (III and V) to provide a bounding on potential risks. Values that exceed 

the selected risk criteria are shown in bold. No 90th percentile risks above ecological criteria 

were identified for either surface impoundment or landfills. No 50th percentile risks above 

human health or ecological criteria were identified for either surface impoundment or landfills. 

Table 3. 90th Percentile Nationwide Probabilistic Risk Results 

COPC

Ingestion of Ground Water

Surface 

Impoundments

Landfills

Cancer Risks

Arsenic III 2 × 10-4

5 × 10-6

Arsenic V 1 × 10-5

7 × 10-8

Noncancer Risks

Arsenic III 5 0.1

Arsenic V 0.4 < 0.01

Lithium 2 --

a

Molybdenum 2 < 0.01

a) Leachate data were not available to model this COPC for landfills.

Surface Impoundments: 

Ingestion of ground water was the only exposure pathway that resulted in risks above 

1x10-5. 90th percentile cancer risks above 1×10-5 were identified for arsenic III (2×10-4). The 
Document submitted to conclude E.O.12866 Review

541

90th percentile noncancer risks above an HQ of 1 were identified for arsenic III (5), lithium (2), 

and molybdenum (2). 

Landfills: 

Ingestion of ground water was the only exposure pathway that resulted in risks above the 

relevant criteria. 90th percentile cancer risks within the full OSWER risk range were identified 

for arsenic III (5×10-6). All 90th percentile noncancer risks were below human health criteria.

High-end risks identified for surface impoundments are consistently higher than those for 

landfills. These results are attributed to the higher infiltration rates through surface 

impoundments, which are driven by the hydraulic head of the ponded water. Median risks for 

both surface impoundments and landfills were substantially lower than both the high-end risks in 

this risk assessment and the median risks modeled in the 2010 Risk Assessment (U.S. EPA, 

2010a). This decrease is attributed primarily to the interception of ground water by surface water 

bodies, which is accounted for in the revised risk assessment to provide a more accurate mass 

balance of constituent mass during transport. It is common for coal-fired utilities to be located 

near water bodies, which are used as a source of cooling water and conveyance of waste. As a 

result, in the majority of model iterations, the interception of ground water by surface water 

bodies resulted in negligible downstream well concentrations.

Based on the results of the probabilistic analysis, EPA concludes that leaching from CCR 

waste management units has the potential to pose risk to receptors. Arsenic and molybdenum are 

the chemical constituents found to pose the greatest risks from surface impoundments, while 

arsenic posed the greatest risks from landfills. Risks from arsenic ingestion are linked to an 

increased likelihood of cancer in the skin, liver, bladder and lungs, as well as nausea, vomiting, 
Document submitted to conclude E.O.12866 Review

542

abnormal heart rhythm, and damage to blood vessels;187 risks from lithium ingestion are linked 

to neurological and psychiatric effects, decreased thyroid function, renal effects, cardiovascular 

effects, skin eruptions, and gastrointestinal effects;188 and risks from molybdenum ingestion are 

linked to higher levels of uric acid in the blood, gout-like symptoms, and anemia.189

4. Sensitivity and Uncertainty Analysis

The modeled probabilistic risks capture the range of current, nationwide CCR disposal 

practices. However, because of the broad scope of the analysis, there are a number of sources of 

variability and uncertainty present. Therefore, to confirm the results of the probabilistic analysis 

and to better understand whether any particular subset of disposal practices drives the risks 

identified, EPA conducted additional sensitivity and uncertainty analyses. 

EPA reviewed the models used, as well as the data and assumptions input into these 

models, to better understand the sources of variability and uncertainty inherent in the 

probabilistic analysis. The Agency then qualitatively and, to the extent possible, quantitatively 

analyzed these sources to understand the potential effects each may have on the modeled risk 

results. During this review, specific attention was focused on the parameters shown to have the 

greatest influence on model results. As a further method of validation, EPA compared the results 

of the sensitivity and uncertainty analyses with proven and potential damage cases. Together 

these analyses and comparisons show that there is a high degree of confidence in the principal 

findings of the probabilistic analysis. However, the review of sensitive parameters revealed some 

specific disposal practices that may result in greater risks than identified in the probabilistic 

modeling.

 

187 Profile for arsenic available online at: www.epa.gov/iris/subst/0278.htm and www.atsdr.cdc.gov/toxprofiles/tp2.pdf

188 Profile for lithium available online at: hhpprtv.ornl.gov/issue_papers/Lithium.pdf

189 Profile for molybdenum available online at: www.epa.gov/iris/subst/0425.htm
Document submitted to conclude E.O.12866 Review

543

Through these additional sensitivity and uncertainty analyses, which explored different 

subsets of national disposal practices, EPA identified the potential for higher risks than those 

identified in the broader, national analysis. In particular, consideration of different waste pH 

values showed higher risks for arsenic at more acidic and basic pH values, as well as additional 

risks for boron, cobalt, fluoride and mercury at these more extreme pH values. Consideration of 

specific liner types showed that ground water risks are driven by disposal in unlined units and, in 

particular, unlined surface impoundments. For these units, EPA identified higher risks for arsenic 

and molybdenum, as well as additional risks for thallium. Clay-lined units were found to pose 

risks that, while lower than unlined units, still fall within the OSWER risk range. Compositelined units were found to be the most protective disposal practice, resulting in risks far below all 

criteria identified in this risk assessment. 

C. Conclusions

Based on the analyses presented in this document, EPA concludes that current 

management practice of placing CCR waste in surface impoundments and landfills poses risks to 

human health and the environment in the range that OSWER typically regulates. On a national 

scale, surface impoundments presented higher risks than landfills. Risks to ecological receptors 

were identified from exposures to aluminum, arsenic, barium, beryllium, boron, cadmium, 

chloride, chromium, selenium and vanadium through direct exposure to impoundment 

wastewater. Risks to residential receptors were identified primarily from exposures to arsenic 

and molybdenum in ground water used as a source of drinking water, but additional risks from 

boron, cadmium, cobalt, fluoride, mercury and thallium were identified for specific subsets of 

national disposal practices. 

Sensitivity analyses on liner type indicate that disposal of CCR wastes in unlined surface 
Document submitted to conclude E.O.12866 Review

544

impoundments and landfills presents the greatest risks to human health and the environment. As 

modeled, the national risks from clay-lined units are lower than those for unlined units, but such 

units can exceed risk criteria at individual sites. Composite liners were the only liner type 

modeled that effectively reduced risks from all pathways and constituents far below human 

health and ecological criteria in every sensitivity analysis conducted. Sensitivity analyses on 

waste type indicate that the acidic conditions that result from codisposal of CCR waste with coal 

refuse and the basic conditions that result from disposal of FGD waste result in higher risks from 

arsenic and other constituents than CCR waste disposed alone. 

The risk results are consistent with the ground water damage cases compiled by EPA. 

These damage cases were primarily associated with unlined units and were most frequently 

associated with releases of arsenic. Recent surveys of the industry indicate the majority of newly 

constructed units are lined, and that that the practice of codisposal with coal refuse has declined. 

However, this risk assessment presents a static snapshot of current disposal practices. While 

newer units may be managed in a more protective manner, older units, which still comprise the 

majority of current units, continue to operate in a manner that poses risks to human health and 

the environment that OSWER typically regulates.

XI. Summary of Damage Cases

EPA has a long history of considering damage cases in its regulatory decisions under 

RCRA. As discussed earlier in this preamble, the statute specifically directs EPA to consider 

“documented cases in which danger to human health and the environment from surface runoff or 

leachate has been proved,” in reaching its Regulatory Determination for these wastes, 

demonstrating that such information is to carry great weight in decisions under this section. 42 

U.S.C. § 6982(n)(4). Damage cases, even if only potential damage cases, are also relevant under 
Document submitted to conclude E.O.12866 Review

545

the third Bevill factor: “potential danger, if any, to human health and the environment from the 

disposal and reuse of such materials.” 42 U.S.C. § 6982(n)(4). In addition, damage cases are 

among the criteria EPA must consider under its regulations for determining whether to list a 

waste as a “hazardous waste.” See 40 CFR 261.11(a)(3)(ix) (“The nature and severity of the 

human health and environmental damage that has occurred as a result of the improper 

management of waste containing the constituent.”). Damage cases generally provide extremely 

potent evidence in hazardous waste listings. In this regard, EPA notes that the number of 

damage cases collected for this rulemaking (157) is by far the largest number of documented 

cases in the history of the RCRA program. 

EPA considers that both proven and potential damage cases provide information directly 

relevant to this rulemaking. First, damage cases provide evidence of both the extent and nature 

of the potential risks to human health and the environment. The primary difference between a 

proven and a potential damage case is whether the contamination has migrated off-site of the 

facility. But the mere fact that groundwater contamination has not yet migrated off-site does not 

change the fact that a potentially harmful constituent has leached from the unit into groundwater. 

Whether the constituent ultimately causes further damage by migrating into drinking water wells 

does not diminish the significance of the environmental damage caused to the groundwater under 

the site, even where it is only a future source of drinking water. As EPA explained in the 

preamble to the original 1979 open dumping criteria, which are currently applicable to these 

facilities, EPA is concerned with groundwater contamination even if the aquifer is not currently 

used as a source of drinking water. Sources of drinking water are finite, and future users’ 

interests must also be protected. (See 44 FR 53445-53448.) ("The Act and its legislative history 

clearly reflect Congressional intent that protection of groundwater is to be a prime concern of the 
Document submitted to conclude E.O.12866 Review

546

criterion....EPA believes that solid waste activities should not be allowed to contaminate 

underground drinking water sources to exceed established drinking water standards. Future 

users of the aquifer will not be protected unless such an approach is taken.")

In the June 21, 2010 proposed rule, EPA presented for public comment an assessment of 

CCR damage cases, and requested comments and other information related to damage cases EPA 

had previously received from industry, environmental groups, and citizen groups. EPA later 

requested public comment on additional damage case information in a Notice of Data 

Availability (NODA) published in the federal register on October 12, 2011 (76 FR 63252). As 

discussed in Section IV of this preamble, the Agency is deferring making a Bevill determination; 

however, EPA is still presenting its findings with regard to damage cases (including information 

submitted during the comment periods for the June 2010 proposal and the October 2011 NODA) 

because as described above, this information supports actions taken in the present final rule.190

A. Damage Cases Presented in June 21, 2010 Proposed Rule 

In the June 2010 proposed rule, the Agency summarized its database on damage cases that had 

expanded since the May 2000 Regulatory Determination.191 This summary included two cases 

of CCR slurry spill caused by surface impoundment dike failures (the 2005 Martins Creek, 

Pennsylvania, and the 2008 TVA Kingston, Tennessee), and two cases involving structural fill 

(the use, between 1995-2007, of CCR in the reclamation of two sand and gravel pits in 

Gambrills, Maryland; and for contouring the Battlefield Golf Course, in Chesapeake, Virginia, in 

 

190 Damage Case Compendium (Technical Support Document on Damage Cases), US EPA, December 

2014.

191 See June 21, 2010 Federal Register -- Appendix to the Preamble: Documented Damages from CCR 

Management Practices.
Document submitted to conclude E.O.12866 Review

547

the early 2000s). In the June 2010 proposed rule, the Battlefield Golf Course site was designated 

as a potential damage case, whereas the other three sites were designated as proven damage 

cases.192

B. Additional Information and Studies

Shortly prior to the publication of the June 2010 proposed rule and immediately 

thereafter, several stakeholder groups provided the Agency with new information on damage 

cases. In November 2009, the Electric Power Research Institute (EPRI) issued a two-volume

draft report193 analyzing the 24 proven and 43 potential damage cases established in EPA’s 2007

damage case report194 accompanying the August 2007 Notice of Data Availability (NODA).195 

EPRI claimed that in the great majority of damage cases there is no record of primary MCL

contaminants migrating off-site that would justify designating them as proven damage cases. 

EPRI also disagreed with several ecologic damage cases that had been predicated on fish 

advisories in Texas, on the grounds that the selenium toxicity standard that triggered these fish 

advisories was later revised by the state, and subsequently the fish advisories were rescinded. In 

February and August 2010, The Environmental Integrity Project (EIP), jointly with other citizen 

 

192 See 75 FR at 35131 for definitions of “proven” and “potential” damage cases.

193 Evaluations of CCP Damage Cases: These two volumes were finalized in July and September 2010, 

respectively: 

http://my.epri.com/portal/server.pt?open=512&objID=413&&PageID=230509&mode=2&cached=true

194 Coal Combustion Waste Damage Case Assessments, July 9, 2007. EPA-HQ-RCRA-2006-0796-0015.

195 Notice of Data Availability on the Disposal of Coal Combustion Wastes in Landfills and Surface 

Impoundments, 72 FR 49714, August 29, 2007.
Document submitted to conclude E.O.12866 Review

548

groups, issued two reports, identifying 70 alleged damage cases.

196, 197

 Fifty of these cases were 

submitted to EPA for the first time. 

In response to EPRI’s report, EPA reassessed the 24 proven damage cases identified in 

EPA’s 2007 Damage Case report, as well as three additional proven damage cases cited in the 

proposed rule. In addition, in response to EIP’s reports, the Agency assessed the 70 alleged

damage cases, to independently confirm the allegations in the report. In reviewing198 these

alleged damage cases, EPA took a number of measures. First, to the extent the information was 

available, EPA consulted tabulated monitoring well data to validate the exceedance data 

presented in comments; and studied well- and waste-unit location maps, geohydrologic studies, 

and groundwater potentiometric maps to validate both whether the wells were up-gradient or 

down-gradient wells and instances of groundwater mounding. EPA also contacted state 

regulators to confirm the reports’ claims of contamination, particularly contamination exceeding 

state or federal water quality standards, and conducted internet research (focusing on state 

regulatory information) pertaining to the sites in question. EPA also thoroughly assessed state

comments submitted to EPA in response to the June 2010 proposed rule and the October 2011 

NODA. Third, EPA identified state or federal administrative measures applied to utilities (e.g., 

consent orders, notices of violation, penalties for non-compliance, etc.) and/or legal motions 

(e.g., law-suits, motions for injunctive relief, and out-of-court settlements) filed by the states or 

citizen groups in order to identify any instances of non-compliance by the utilities that have 

 

196 In Harm’s Way: Lack Of Federal Coal Ash Regulations Endangers Americans and Their Environment. 

Environmental Integrity Project, EarthJustice, and Sierra Club:

http://www.environmentalintegrity.org/news_reports/08_26_10.php.

197 Out of Control: Mounting Damages from Coal Ash Waste Sites. Environmental Integrity Project and 

EarthJustice: http://www.environmentalintegrity.org/news_reports/news_02_24_10.php

198 See Assessment of Previously Identified Proven Damage and Recently Alleged Damage Cases, 

October 2010.
Document submitted to conclude E.O.12866 Review

549

resulted in documented impacts to water resources.

EPA’s review confirmed that 13 of the 27 damage cases previously designated as proven 

did meet the criteria used by EPA for identifying proven damage cases; however, EPA also 

found that six of the 27 cases only meet the criteria for a potential damage case, while the 

remaining eight cases were altogether rejected (i.e., EPA determined that a damage case has not 

occurred, and/or test of proof criteria were not satisfied, and/or CCR was not the only or 

predominant waste component). Regarding the 70 alleged damage cases in the two EIP reports,

EPA concluded that ten of them qualify as proven damage cases, 45 as potential damage cases,

and the remainder were either rejected or, due to the lack of adequate information, defined as 

indeterminate. 

In November 2011, the Utility Solid Waste Activities Group (USWAG) submitted to the 

docket of the October 2011 NODA a critical review of EIP’s 70 alleged damage cases from 

2010. USWAG’s review concluded that “the overwhelming majority of the allegations 

regarding the 70 sites...fail to provide the requisite ‘test of proof’ documentation necessary for 

EPA to characterize virtually any of the sites as proven damage cases.” Also, in November 2011 

EIP submitted to the docket of the October 2011 NODA a report alleging 20 new damage 

cases.199

Following review of the comments on the proposed rule and the October 2011 NODA, 

EPA has revisited some of its earlier damage case findings. Our post-proposal studies have 

resulted in: 1) rejection of 17 of the previously-established and newly-alleged damage cases, 

 

199 EPA-HQ-RCRA-2011-0392-0259. Nineteen of the cases involve groundwater impact, and one 

involves soil contaminated by the placement of coal ash and clinkers from train engine boilers for railroad 

tracks bed. A hard copy of the report, Risky Business: Coal Ash Threatens America’s Groundwater 

Resources at 19 More Sites, was issued on December 12, 2011
Document submitted to conclude E.O.12866 Review

550

either due to inappropriate scope (e.g., oil combustion waste, non-utility CCR, or CCR disposedoff in abandoned coal mine pits), co-mingling with non-CCR waste, or inadequate information to 

ascertain that contaminants are derived from CCR; 2) two of the damage cases that had been 

previously designated as ‘rejected’ in EPA’s 2007 damage case report were re-categorized as 

proven damage cases and six others were re-categorized as potential damage cases; and 3) one 

damage case site reported in Risky Business occurred next to a site that had already been 

previously reported. 

In summary, at the present time the Agency has established 40 proven and 113 potential 

damage cases. In addition, the rulemaking docket contains four additional, state-endorsed 

damage cases from Wisconsin. While EPA has insufficiently-detailed information (including the 

extent, if any, that the contaminants have migrated off site) to designate these four additional 

sites as potential or proven, because the state has identified them to us as damage cases, we have 

included them in our overall total of 157. 

C. Stakeholder Comments on Damage Cases 

All of the comments submitted by stakeholders to the dockets of the proposed rule and 

the October 2011 NODA, as well as EPA’s responses, are included in the Technical Support 

Document to CCR Damage Cases which is available in the RCRA docket supporting this rule. 

The following is a summary of the salient comments submitted by the various stakeholder 

groups. 

1. Utility Industry’s Comments 

EPA received several comments from utilities arguing that an incident should not be

considered to be a “damage case” if the environmental damage has been addressed or is no 

longer occurring and/or if the State Director is satisfied that no further action is required. (Note: 
Document submitted to conclude E.O.12866 Review

551

For those damage cases known to the Agency prior to EIP’s 2010 reports, remediation is 

completed or underway at all sites where remediation was known to be required.) These 

commenters also argued that EPA should disregard cases in which there are no downstream 

contaminant receptors to be harmed by the contamination. These commenters also alleged that 

only “proven” damage cases should be considered to be relevant as only these are “documented 

cases in which danger to human health or the environment from surface runoff or leachate has 

been proved,” 42 U.S.C. § 6982(n)(4). . 

Industry commenters also made a number of other points. They stated that most damage 

cases occurred in older facilities commissioned before current state landfill regulations were 

promulgated, where most waste units lack liners and leachate collection systems, and that in 

most cases, exceedances of state or federal water quality standards were contained on site, and 

these exceedances are mostly for constituents (e.g., sulfate and boron) that do not have federal,

health-based drinking water quality standards. These commenters also claimed that the number 

of proven damage cases is very sparse: of the 24 proven damage cases in EPA’s 2007 report,200

they argued that only three had documented off-site groundwater exceedances of health-based 

MCLs that can be attributed to CCR impacts. They also claimed that of the 70 alleged damage 

cases in EIP’s 2010 reports (In Harm’s Way and Out of Control), 64 did not meet EPA’s “test of 

proof” criteria for characterizing the site as a proven damage case. For the remaining six sites,

where the allegations on their face arguably met EPA’s definition of a proven damage case, these 

commenters claimed that these cases should be discounted because they involved sites that are 

either no longer active or where the damages had been already remediated or are undergoing 

remediation with federal/state oversight. These commenters also said that 12 of the 70 EIP-

 

200 Coal Combustion Waste Damage Case Assessments, ibid.
Document submitted to conclude E.O.12866 Review

552

alleged damage cases were previously addressed in EPA’s 2007 Damage Case report, and of 

these, five sites had been rejected by the EPA due to lack of evidence of damage or lack of 

evidence of damage uniquely associated with CCR, and seven sites had been characterized as 

indeterminate due to insufficient information. According to these commenters, no new 

information regarding these 12 sites was contained in the two EIP reports that warrants their 

designation as proven damage cases.

201

2. Individual State Comments

EPA also received a significant number of comments from individual states. In their 

comments, many of the states addressed selected damage cases that occurred within their 

jurisdiction, subject to their authority. Several states agreed with EPA’s assessment of the 

damage cases; for instance, Wisconsin and Michigan complimented EPA’s database of damage 

cases. Other commenters agreed with some of the newly alleged damage cases’ reports of 

groundwater contamination exceeding regulatory standards, but disagreed with EIP’s 

conclusions that enforcement was inadequate, tardy, or absent. According to some state 

commenters, enforcement was not necessary or appropriate in those instances. For example, 

some states (e.g., North Carolina, Oklahoma, Tennessee, and Florida) argued that the 

contamination did not pose public health risks because the contaminants were confined to stateestablished Compliance Boundaries (known also as Groundwater Mixing Zones)202 and/or 

because there was no evidence the contamination had migrated off-site. Several other states (e.g., 

Maryland, Virginia, and Texas) confirmed EPA’s established damage cases as well as some of 

 

201 EPA-HQ-RCRA-2011-0392-0211, ibid.

202 A Zone of Discharge or Zone of Mixing is a three dimensional region containing groundwater being 

managed to mitigate impairment caused by the release of contaminants from a waste disposal site; by 

definition, it is inside the detection boundary area, hence it is exempt from compliance with MCL and 

SMCL standards (e.g., in Florida, Illinois, South Carolina, Tennessee, North Carolina, and Pennsylvania).
Document submitted to conclude E.O.12866 Review

553

the newly alleged damage cases, but claimed that these cases were associated with presently 

outdated practices, and that regulatory requirements have since been revised to prohibit such 

practices. Two states (South Dakota and Pennsylvania) confirmed that contamination above 

federal or state regulatory standards had occurred, but attributed the contaminant(s) to sources 

other than CCR units, e.g., coal mining pits associated with coal refuse; and/or nearby, upgradient unlined MSWLFs, cooling water evaporation ponds, or natural background soil 

compositions. For certain cases, the states explained that required assessment monitoring was 

still ongoing to establish the source, scope, and extent of the contamination, and so had reached 

no conclusions about the specific allegations (North Carolina, North Dakota, and Tennessee). 

Finally Ohio acknowledged that the extent of groundwater contamination risk within the state is 

poorly-documented due to the scarcity of monitoring wells down gradient from unlined disposal 

units. 

3. State Association Comments

The Association of State and Territorial Solid Waste Management Officials 

(ASTSWMO) argued that the 24 proven damage cases reported in EPA’s 2007 Damage Case

report do not reflect current land disposal practices, and so are irrelevant to the proposed rule. 

For example, disposal “units” involved in several damage cases included five sand and gravel 

pits, two quarries, and one lake impoundment. ASTSWMO commented that half of these sites 

began operating in 1970 or earlier, including at least six sites that began operating in the early 

1950s. ASTSWMO claimed that much of the information cited in the two EIP 2010 alleged 

damage case reports is incomplete, incorrect and/or misleading. For example, their comments 

alleged that EIP failed to provide pertinent information on specific monitoring wells, 

sample/analytical dates, and hydrogeological data. ASTSWMO also claimed that many of the 
Document submitted to conclude E.O.12866 Review

554

assumptions about groundwater flow were based on a topographic maps rather than on 

potentiometric maps that are based on subsurface groundwater flow data. They also claim that 

data in state files contradicted claims in the reports, and that EIP’s reports contained numerous 

technical errors, such as reporting values for naturally occurring constituents as contamination, 

reported data without distinguishing between down-gradient and up-gradient wells, ignoring the 

potential contribution from sources other than CCR-related units (e.g., coal mining legacy), and 

claims that information provided by state program staff was misconstrued/misrepresented.

4. Citizens Group Comments

Citizen groups generally argued that the fact that damage has occurred should be part of 

the weight of evidence documenting the potential for harm at all CCR disposal sites, without 

regard to whether the damage cases were categorized as “proven” or “potential.” These 

commenters also raised a number of arguments in direct response to the comments provided by 

the utilities and the states. For example, these commenters argued that the presence of 

downstream receptors is a valid factor to consider when setting priorities for mitigating damage, 

but does not justify allowing contamination to migrate off of the disposal site. These 

commenters claimed that about one-fifth of EPA’s damage cases preceding the 2010 EIP reports 

show evidence of contamination of private and public drinking water wells. In addition, these 

commenters allege that state regulatory agencies have done little to respond to contamination 

from CCR disposal sites, and, even in those cases where action has been taken, rarely is any 

action taken beyond assessment monitoring. According to these commenters, off-site monitoring 

has only occurred at a limited number of sites, and mostly such monitoring was performed

voluntarily by the utilities and was not reported to state regulators. These commenters also 

claimed that although less than half of EPA’s damage cases preceding the 2010 EIP reports 
Document submitted to conclude E.O.12866 Review

555

involve active landfills, almost three-quarters of the newly alleged damage cases (EIP’s 2010 

reports) involve active landfills. They further alleged that a large majority of EPA’s surface 

impoundment damage cases preceding the 2010 EIP reports are active sites, indicating that the 

absence of liners is contributing to the contamination problems. They noted that one quarter of 

the damage cases in EIP’s 2010 reports involved units with liners, indicating that the mere 

presence of any liner provides no assurance that migration of contaminated groundwater from a 

waste unit is not occurring. Overall, they claimed that surface impoundments remain “woefully 

unregulated” when compared to landfills. Over one third of EIP’s alleged groundwater damage 

cases show migration of contamination off-site. Also, a quarter of EPA’s damage cases 

preceding the 2010 EIP reports involve contamination of surface water, and 15 percent of these

damage cases show ecologic damage. Finally, these commenters note that several of the 

Secondary Contaminant Maximum Levels (SMCLs) constituents still might cause harm to 

recipients residing next to CCR disposal sites. 203

D. Response to Key Stakeholder Comments 

In many instances EPA did not have access to information that would either substantiate 

or refute the claims in EIP’s reports. In many instances public commenters submitted 

information that clarifies, rebuts or otherwise calls into question some of the allegations 

contained in the various damage case reports. For example, there are instances in which claims 

were made that a contaminant plume had migrated offsite even though there were no offsite 

monitoring wells to confirm the claim. Due to the dearth of groundwater monitoring on 

 

203 Examples include boron’s One-Day and Ten-Day Health Advisory (3.0 mg/L) and the Longer Term 

Health Advisory (2.0 mg/L) levels for children; manganese’s Long Term Health Advisory (LTHA: 0.3 

mg/L) level; and sulfate’s Drinking Water Advisory (DWA: 500 mg/L) level in groundwater have been 

exceeded each in between over 60 and close to 80 of both the alleged and damage case sites and those 

sites preceding the 2010 EIP reports. 
Document submitted to conclude E.O.12866 Review

556

facilities’ boundaries (or beyond) EPA could not identify offsite plume migration for most sites, 

except in the rare instances drinking water wells had been contaminated. Consequently, only 10 

of the 70 alleged cases submitted by EIP in 2010 were designated as proven damage cases. 

In addition, factual errors were identified in certain instances; for example, certain 

allegations of groundwater contamination were based on surface water standards (rather than 

groundwater standards). Corrections or updated facts are reflected in EPA’s damage case 

assessment. Nevertheless, EPA was able to validate a significant number of EIP’s claims; for 

example, as of 2011, EPA was able to confirm that a significant portion of the damage cases in

EIPs 2010 report involved both landfills and surface impoundments, most of which involved 

units with either no liner or a substandard liner system. And for many of EIP’s damage cases, 

EPA was able to confirm sufficient details to classify them as potential damage cases. 

However, EPA disagrees with most of the arguments minimizing the significance of the 

damage case record. First, cases where contamination has been remediated remain relevant to 

this rulemaking. EPA is relying on the damage cases to evaluate the extent and nature of the 

risks associated with particular CCR management practices. Facts demonstrating the 

consequences from particular activities therefore remain relevant, particularly (although not 

solely) where the management practices continue to occur. In other words, what matters in this 

regard are facts that provide information on the reasons that unit leaked, the particular 

contaminants that were present, the levels of those contaminants, and the nature of any impacts 

caused by that contamination. None of these facts are affected by whether the damage is 

ultimately mitigated or remedied. This is entirely consistent with RCRA section 8002(n), which 

requires EPA to evaluate the “potential danger, if any, to human health and the environment 

from the disposal and reuse of such materials” in addition to “documented” damage cases. 42 
Document submitted to conclude E.O.12866 Review

557

U.S.C. §§ 6982(n)(3)-(4). Accordingly, the fact that any contamination has subsequently been 

remediated is not a basis for disregarding a damage case. Moreover, EPA is not relying on these 

damage cases to evaluate the adequacy of state programs, although it may ultimately provide 

information relevant to such findings. Therefore the adequacy of the state’s response, or the lack 

thereof, is also not relevant to whether particular damage cases are appropriately considered as 

part of this rulemaking. 

EPA also disagrees that only the presence of receptors within the impact sphere of a 

contaminating facility merits consideration of a particular damage case. EPA’s longstanding and 

consistent policy across numerous regulatory programs has been that groundwater contamination 

is a significant concern that merits regulatory action in its own right, whether or not the aquifer is 

not currently used as a source of drinking water. Sources of drinking water are finite, and future 

users’ interests must also be protected. The absence of current receptors is therefore also not an 

appropriate basis on which to discount damage cases. And for all of the reasons discussed 

above, EPA also disagrees that only exceedances of health-based standards of contaminants that 

have migrated off-site (i.e., only proven damage cases) should be accounted for as part of this 

rulemaking. 

The Agency also disagrees with the claims that the number of damage cases is “sparse,” 

the majority of which involve only “outdated CCR management practices” in older facilities, and 

therefore are not relevant to determining the current risks from CCR mismanagement. Even 

assuming that only “proven” damage cases were relevant, to date, EPA has confirmed a total of 

40 proven damage cases, which is hardly “sparse.” And when “potential” damage cases are 

considered, the totals rise to 157; this is the largest number of damage cases in the history of the 

RCRA program. Further, these numbers likely underestimate the true number of cases in which 
Document submitted to conclude E.O.12866 Review

558

CCR units are contaminating groundwater. In reality, the damage case record represents only a 

subset of those CCR waste units that have effective groundwater monitoring. As discussed in 

Unit IV.A., a significant portion of CCR surface impoundments still lack groundwater 

monitoring, and only approximately 80% of the recently commissioned impoundments (i.e., 

since about 1994) have groundwater monitoring. 

In addition, under many state programs existing impoundments are exempt from 

groundwater monitoring and once monitoring is put in place, new damage cases quickly emerge. 

This is illustrated by two lines of evidence: first, in the wake of the 2008 TVA Kingston CCR 

spill two states required utilities for the first time to install groundwater monitoring. Illinois 

required facilities to install groundwater monitoring down gradient from their surface 

impoundments. As a result, within only about two years, Illinois detected seven new instances of 

primary MCL exceedances and five additional instances with exceedances of SMCLs. The data 

for all twelve sites were gathered from onsite; it appears none of these facilities had been 

required to monitor groundwater off-site, so whether the contamination had migrated off-site is 

currently unknown.204 Similarly, North Caroline required facilities to install additional down 

gradient wells. In January 2012, officials from the North Carolina Department of Environment 

and Natural Resources disclosed that elevated levels of metals have been found in groundwater 

near surface impoundments at all of the State’s 14 coal-fired power plants.

205

 

 

204 See EIP's December 2011 Risky Business: Coal ash Threatens America's Ground Water Resources at 

19 More Sites, docket document EPA-HQ-RCRA-2011-0392-0259, Appendix A3.

www.environmentalintegrity.org/.../121311EIPThirdDamageReport.pdf and Illinois EPA’s Ash 

Impoundment Strategy Progress Reports, February 10 and October 2011, accessed Online July 15, 2014: 

http://www.epa.state.il.us/water/groundwater/publications/ash-impoundment-progress.pdf and

http://www.epa.state.il.us/water/ash-impoundment/documents/ash-impoundment-progress-102511.pdf

205 Groundwater Monitoring Data for Coal Ash Ponds, NC DENR: http://portal.ncdenr.org/web/wq/hottopics/coalashregulation/gwatermonitoring. Accessed Online July 15, 2014.
Document submitted to conclude E.O.12866 Review

559

Second, states with effective programs for groundwater monitoring tend to have a larger 

record of damage cases (e.g., Wisconsin, nationally ranked as the 32nd CCR disposer in 2011, has 

14 damage cases) as compared to states with less stringent groundwater monitoring requirements

(e.g., Texas, nationally ranked as the second largest CCR disposer in 2011, has only three 

confirmed, potential damage case).

Nor is it accurate that the majority of these damage cases involve older units that no 

longer reflect current management practices or state requirements. The commenters point to the 

fact that the majority of cases involve units constructed before current state landfill regulations 

were promulgated, and thus lack liners and leachate collection systems. EPA agrees that the 

majority of cases do involve such units, but this hardly reflects “outdated” or irrelevant 

management practices. As discussed in Unit IV.A, the majority of CCR continues to be 

managed in older (i.e., constructed pre-1994) units that lack liners and leachate collection 

systems, and will in fact continue to be managed in such units for at least the near future. 

Approximately six percent of the waste units associated with groundwater impacts have been 

constructed from 1990 onwards. Considering there is a lag time between the construction of 

many of the disposal units and the first detection of their groundwater impact by subsequently 

installed groundwater monitoring wells, the absence of damage cases associated with newer units 

is neither unexpected nor dispositive as to the level of risk such units pose. 

Finally, a number of other factors support the conclusion that the current number of 

damage cases likely underestimate the current risks. First, the combined effect of a number of 

current state regulatory provisions is to decrease the instances in which off-site contamination 

will be detected (or on-site contamination will need to be remediated). For example, several 

states have adopted ”buffer zones” where certain standards may not apply; Florida designates 
Document submitted to conclude E.O.12866 Review

560

certain areas as a “Zone of Discharge” (ZOD), in which numerical primary and secondary 

drinking water standards do not apply; this exemption extends even beyond the ZOD, unless 

ordered specifically by the state. In addition, secondary maximum contaminant levels (SMCLs) 

are not applicable to existing industrial facilities discharging to groundwater in the state.206 In 

other instances, states grant waivers to certain facilities that exceed health-based standards 

several-fold.207 Certain states (e.g., Indiana) consider surface impoundments as temporary 

storage facilities as long as they are dredged on a periodic basis (e.g., annually). Under these 

states’ rules, such impoundments are exempt from any solid waste regulations that would require 

groundwater monitoring, and from requirements for corrective action.208 Such requirements are 

likely to decrease the instances in which contamination above an MCL has migrated off-site will 

be detected. Second, the record documents several instances where, once the contaminant 

plume has migrated off-site and impacted private water wells, the utility has purchased these 

properties, thereby rendering the off-site contamination, “on-site.” At times, this practice (which 

is condoned by the state) has expanded the ZOD to well beyond its original boundary. Once the 

status of the contaminant plume changes from off-site migration, which typically requires 

remedial action, back to onsite containment, this can affect the kind of corrective action the state

requires of the utility (or indeed whether any will be required). 

E. Characterization of Impacts Associated with CCR Disposal Units

 

206 Illinois uses a similar concept: Groundwater Mixing Zone; North Carolina waives any compliance 

requirements for constituents in exceedance of the state’s groundwater standards that are confined to 

monitoring wells within the Compliance Boundary; and in Pennsylvania and Tennessee, state laws do not 

require state response to onsite exceedances of secondary MCLs.

207 The observations cited in the following pertain to groundwater quality. Regarding surface water 

quality, NPDES permits in many states commonly have very limited requirements for monitoring 

discharge constituents, excluding all or most of the heavy metals.

208 E.g., Duke Energy’s Gibson Generating Station, Princeton, Indiana, a proven damage case.
Document submitted to conclude E.O.12866 Review

561

1. CCR Waste Unit Types Associated With Damage Cases

EPA’s documented record of confirmed damage cases is dominated by wet-disposal and 

treatment modes: surface impoundments, cooling ponds, and artificial wetlands constitute close 

to half of the total number of implicated waste units. In comparison, dry disposal modes such as 

landfills, sand and gravel pits, storage piles for coal ash and FGD, and certain structural fills 

account for about one third of the confirmed damage cases.

209 Sand and gravel pits and quarries 

as well as structural fills, comprise about ten percent of all the unit types that are associated with 

damage cases. 

2. Contaminants of Concern (COCs)

Because the list of constituents to be monitored in groundwater varies from permit to 

permit and among states, accurate estimates of the frequency of constituents associated with 

groundwater impacts nationwide cannot be made with confidence. Based on the available 

monitoring records, the most prevalent contaminant among the primary MCLs identified in 

damage cases is arsenic, whereas the most prevalent contaminants identified among the 

secondary MCLs are sulfate and boron. Similarly, disparities from one permit to another as to 

which constituents are monitored in NPDES discharges from CCR impoundments limit EPA’s 

ability to identify trends associated with contaminants of concern. Based on the Agency’s record 

of all of the confirmed damage cases, it can be only established that the most prevalent COCs 

with respect to Primary Water Quality Criteria (WQCs) exceedances in surface water, and/or of 

cleanup standards in sediments and soils are selenium and arsenic, and for Secondary WQCs or 

 

209 Facilities with both wet and dry disposal waste units are implicated in less than twenty percent of the 

cases.
Document submitted to conclude E.O.12866 Review

562

cleanup standard exceedances, are boron and iron.

210

The high mobility of boron and sulfate explains the prevalence of these constituents in 

damage cases that are associated with groundwater impacts. Damage cases impacting surface 

water that have also a documented ecologic impact comprise the largest subset of proven damage 

cases (over 40 percent). The most prevalent COC here is selenium, the bioaccumulative effects 

of which have caused abnormal mortality rates and sublethal effects such as histopathological 

changes and damage to reproductive and developmental success, adversely impacting aquatic 

populations and communities of fish and amphibians. Such impacted communities, residing both 

in lentic (e.g., cooling water lakes) and lotic (e.g., small to medium-size streams) settings that 

receive regulated (i.e., via permitted outfalls) and unregulated (i.e., via seepage) discharge from 

CCR impoundments were documented and rather extensively studied in several sites (e.g., in 

Texas, North Carolina, and South Carolina).211, 212

There are fewer recorded instances of surface water damage cases involving the heavy 

metal COCs such as antimony, beryllium, mercury, and thallium than of groundwater damage 

cases. It is unclear whether this genuinely reflects lower potential risks via this route of exposure. 

Intrinsic differences between the chemical and physical parameters of surface water and 

 

210 For a list of the key metals found in CCR wastewater and examples of the environmental concerns 

associated with them, see Steam Electric Power Generating Point Source Category: Final Detailed Study 

Report; EPA 821-R-09-008, October 2009: http://water.epa.gov/scitech/wastetech/guide/steamelectric/upload/Steam-Electric_Detailed-Study-Report_2009.pdf

211 In validation of the findings of the Risk Assessment accompanying this rule, EPA has documented 

numerous damage cases where selenium in CCR wastewater discharge into surface waters triggered the 

issuance of fish-consumption advisories as well as selenium MCL exceedances in ground water, 

suggesting that selenium concentrations in CCR wastewater constitute a human health risk.

212 According to the draft Steam Industry’s Effluent Guidelines EA, the steam electric power sector is 

responsible for a significant fraction of the toxic pollutants reported to be discharged in industrial 

National Pollutant Discharge Elimination System (NPDES) permits.
Document submitted to conclude E.O.12866 Review

563

groundwater (e.g., the higher redox potential and the larger flow-rate of the former) would 

accelerate the removal of many metals from surface water through precipitation and/or 

adsorption and facilitate a greater dilution. However, as noted, NPDES permits in many states 

commonly have very limited requirements for monitoring discharge constituents, excluding all or 

most of the heavy metals, so this cannot be ruled out as at least a contributing factor213 

3. Failure/Impact Modes

The CCR damage case record shows the following prevalent impact modes (more than 

one possible impact type per generating facility site is possible): slightly over half of the 

recorded impact cases are associated with groundwater; about ten percent are associated with 

surface water, which quite frequently is also accompanied by documented ecological impacts 

and/or with the contamination of soils and/or river sediments; over one third are associated with 

both groundwater and surface water impacts; and about four percent are associated with 

catastrophic surface impoundment failures. 

The established damage case record includes ten sites involving exceedances of primary 

MCLs that have impacted drinking water wells. In all of these cases, the implicated utility 

provided alternative potable water to well water users.214 Three of the damage cases were listed 

 

213 This issue is illustrated by the very limited monitoring record on mercury exceedances in surface water 

as compared to the extensive documentation of mercury impacts revealed in studied surface water that 

receive steam industry effluents. These studies have documented fish and invertebrates exposed to 

mercury from CCR wastewater exhibiting elevated levels of mercury in their tissues and developing 

sublethal effects such as reduced growth and reproductive failure. For an excellent summary of surface 

water ecologic and human health risks and impacts study results, see the cited Steam Electric Power study 

report.

214 These proven damage cases include eight cases where the utility was directed by the state to provide 

an alternative water supply (NIPSCO Yard 520, IN; Constellation Energy Gambrills, MD; Don Frame 

Trucking, NY; Bruce Mansfield, PA; Trans Ash Landfill, TN; VEPCO Chisman Creek, VA; Stoneman, 

WI; and WEPCO Highway 59, WI); and two instances in which the utility provides substitute water to 
Document submitted to conclude E.O.12866 Review

564

on the National Priority List as Superfund sites,215 and one is a Superfund Alternative (SA) 

site.216 In the course of reassessing the pre-EIP 2010 damage cases and vetting EIP’s alleged 

damage cases, the Agency rejected two other Superfund damage cases, because in addition to 

CCR, these site had also accepted large volume of non-CCR waste.217

Four major releases of CCR sludge associated with surface impoundment dike or pipe 

failure resulted in significant coal slurry releases,218 causing fish kills and other ecologic damage, 

and in some instances damage to infrastructure. In the Clinch River spill, for instance, it was 

estimated that 217,000 fish were killed in a 90-mile stretch of the river in Virginia and

Tennessee. The Clinch River plant coal ash had a high free lime content, which reacted with 

 

residents on a voluntary basis (Gibson Station, IN, and Colstrip, MT). In three additional, potential 

damage cases (Oak Creek, WI; Battlefield Golf Course, VA; and Joliet Station 9, IL), the utilities provide 

substitute water – out of abundance caution – to adjacent residential properties whose water wells were 

impacted by secondary MCL exceedances, and in two additional cases, the electrical utility was instructed 

by state regulators to provide substitute water to residential properties which either have had their 

drinking water wells impacted by trace amounts of thallium, within the State and the federal standards 

(Asheville, NC) or by exceedances of boron (Sutton, NC). Finally, in one case (Belews Creek, NC) the 

electric utility agreed to co-fund upgrading of potable water treatment plants in two municipalities to 

eliminate trihalomethanes, a carcinogenic by-product of power plant scrubber, bromide-containing river 

water subject to water treatment employing chlorine.

215 OU-12, Oak Ridge, Tennessee (an NPL site between 1989 and 1997); VEPCO, Chisman Creek, 

Virginia (an NPL site between 1983 and 1988); and the Lemberger Landfill, Wisconsin (1986 to present).

216 Town of Pines Groundwater Plume, Indiana (SA: 2003-Present): 

http://www.epa.gov/region5/superfund/npl/sas_sites/INN000508071.htm. The Site is not listed on the 

National Priority List (NPL) although it qualifies for such listing. The SA approach uses the same 

investigation and cleanup process and standards that are used for sites listed on the NPL, while it can 

potentially save the time and resources associated with listing a site on the NPL. As long as a PRP enters 

into an SA approach agreement with EPA, there is no need for EPA to list the site on the NPL. 

217 These are the formerly proven damage case of Salem Acres, Massachusetts (originally addressed in the 

2007 Coal Combustion Waste Damage Case Assessments Report), and Industrial Excess Landfill, 

Uniontown, Ohio, an alleged damage case submitted by EIP in In Harm’s Way, 2010.

218 These catastrophic releases involved the release of 1.1 x 109

, 2.7 x 108, 1.3 x 108, and 1 x 108 gallons of 

CCR slurry at the spills of the 2008 Kingston TVA, Tennessee; the 2014 Dan River, North Carolina; the 

1967 Clinch River, Virginia; and the 2005 Martins Creek, Pennsylvania, respectively.) In addition, the 

possible ecologic impacts of two consecutive, 30 million gallons each, of CCR slurry releases (in 2007 

and 2008) by the Eagle Valley power plant in Indiana have not been assessed.
Document submitted to conclude E.O.12866 Review

565

water in the settling pond to form an alkaline calcium hydroxide. As a result, during the release, 

pH was elevated to levels as high as 12.7. The high-toxicity shock also decimated benthic macroinvertebrate populations for a distance of over three miles below the spill site, and snails and 

mussels were eliminated for over 11 miles below the Clinch River power plant. 

As demonstrated in the aftermath of the 2008 coal ash spill in TVA Kingston, Tennessee, 

large impoundment dike breach incidents result in impacts to soil and river sediments. In a study 

conducted few months after the spill, Emory River’s downstream sediments showed high 

mercury concentrations similar to those detected in the coal ash (115-130 μg/kg).219 According to 

this study, the ecological effects of mercury in the coal ash and sediments depend on the 

chemical mobility of mercury in the solids and the potential for mercury methylation in the 

impacted area. Previous studies have shown that sulfate addition can promote methylation in 

freshwater ecosystems by stimulating sulfate reducing bacteria, the primary organisms 

responsible for producing methylmercury in the environment. In coal-ash-containing waters, a 

10- to 20-fold increase in SO4

-2

concentrations was observed in the Emory River Cove area 

relative to unaffected upstream sites. Therefore, the methylation potential of mercury from this 

material could be high because the coal ash also provides an essential nutrient (SO4

-2

) that 

encourages microbial methylation. In addition, leaching of contaminants from the coal ash 

caused contamination of surface waters in areas of restricted water exchange and slight elevation 

down gradient. The accumulation of arsenic-rich fly ash in bottom sediment in the Emory

River’s aquatic system could cause fish poisoning via both food chains and decrease of benthic 

 

219 Survey of the Potential Environmental and Health Impacts in the Immediate Aftermath of the Coal Ash 

Spill in Kingston, Tennessee. Laura Ruhl et al., Environ. Sci. Technol. Published online on May 4, 2009. 

Volume 43 (16), pp 6326–6333: http://pubs.acs.org/doi/abs/10.1021/es900714p
Document submitted to conclude E.O.12866 Review

566

fauna that is a vital food source. Another recent study estimates that the damage to fish and other 

wildlife incurred by both permitted and unpermitted CCR effluent discharge at some 22 sites 

amounts to over $2.3 billion.220

a. Construction Year and First Detection Year

Slightly over half of the CCR waste units identified as the source of groundwater 

contamination in the damage cases were commissioned in the 1970s and 1980s, two boom 

decades of coal-fueled power generation growth in the U.S. Whereas the majority of the CCR 

waste units associated with damage cases were constructed before 1990, approximately six

percent of the units in the damage cases (where the commissioning date is known) became 

operational after 1990. For 61 units with known commissioning dates, the median lag time 

between commissioning and the first detection of impact to groundwater is about 20 years. 

However, considering the large range of lag time values (between less than one year and 50 

years) the recorded median lag time most probably reflects additional variables. Possible 

variables include monitoring wells that were installed after many of the waste units were already 

well into their operating stage, and the variable hydraulic conductivity of the impoundment’s 

substrate (including the effectiveness of its liner, if any), both of which will determine how 

quickly groundwater contamination is first detected. Overall, the evidence about the lag time 

between the commissioning of a waste unit and the first detection of the impact of its leakage 

implies that most likely there are prospective damage cases that have not yet been identified, 

challenging industry’s claims that the damage cases represent the legacy of a bygone regulatory 

regime.

 

220 A. Dennis Lemly and Joseph P. Skorupa: Wildlife and the Coal Waste policy Debate: Proposed Rules 

for Coal Waste Disposal Ignore Lessons from 45 Years of Wildlife Poisoning. Environ. Sci. Technol., 27 

July, 2012.
Document submitted to conclude E.O.12866 Review

567

b. Liners

Of the waste units implicated in damage cases to groundwater with information on liners, 

over 90 percent have either no liners, some sort of ash-based liners (e.g., Poz-O-Tec, an 

FGD/lime-conditioned liner), or only partial- or high- permeability (e.g., concrete) liners. The 

majority of the remaining CCR waste units is either clay-lined and/or has a recognizably-failed 

liner. Considering that over a half of CCR waste units associated with groundwater impacts were 

constructed in the 1970s and 1980s, historic information on liner prevalence and composition is 

highly pertinent. According to the February 1988 Report to Congress on coal combustion wastes 

(“RTC I”), before 1975 less than 20 percent of all generating facility units managed their CCR in 

lined disposal units, and in generating facility units constructed since 1975, the share of lined 

units grew to over 40 percent.221 However, as late as in the mid-1980s, about three-quarters of all 

CCR units (87 percent of surface impoundments and 39 percent of landfills) were still unlined.222

In the mid-1990s, the estimated prevalence of unlined landfills still ranged between 43-57 

percent, and between 71-72 percent for surface impoundments.223 According to the March 1999 

Report to Congress on wastes from the combustion of fossil fuels (RTC II), the most prevalent 

liner type was compacted clay (about one-half of all lined landfills, and about 80- percent of all 

 

221 Wastes from the Combustion of Coal by Electric Utility Power Plants (First Report to Congress), 

EPA/530-SW-88-002, February, 1988, pages 4-30 to 4-33: 

http://www.epa.gov/osw/nonhaz/industrial/special/fossil/coal-rtc.pdf.

222 These statistics are based on about 42 percent of the total CCR disposal units at that time, for which 

liner information was available. RTC I attributes this low percentage to the common practice of disposal 

in off-site units, for which liner information was not available.

223

 Based on three different partial surveys cited in the Second Report to Congress (RTC II, 1999): 

Wastes from the Combustion of Fossil Fuels, Volume 2 – Methods, Findings, and Recommendations

(Second Report to Congress), EPA 530-R-99-010, March 1999: 

http://www.epa.gov/osw/nonhaz/industrial/special/fossil/volume_2.pdf
Document submitted to conclude E.O.12866 Review

568

lined surface impoundments). Composite and/or synthetic liners were significantly more 

prevalent in landfills than in surface impoundments. Based on recent EPA data,224 the use of 

liners is still more prevalent in landfills than in surface impoundments. 

c. Geographic Distribution

Close to 70 percent of all the established damage cases occur in EPA Regions 5, 4, and 3 

(in descending frequency, Region 5: 34 percent; Region 4: 28 percent; and Region 3: seven 

percent).

225 This distribution correlates well with the regional distribution of unlined CCR 

disposal units in the mid-1980s.226

d. Current CCR Waste Unit Status

As of mid-2011, close to half of the combined (proven and potential) damage case CCR 

waste units were still active; about a quarter were inactive due to either closure of the individual 

disposal unit, a fuel switch (e.g., from coal to gas) by the generating facility, or the 

decommissioning of the facility. Another quarter or so represented power generating facilities 

where CCR waste units (primarily impoundments) that failed to comply with state requirements 

had been closed and replaced by other, new disposal units, and/or the generating facilities 

switched from wet- to dry disposal. Since mid-2011, the percentage of inactive CCR disposal 

 

224 EPA compiled the baseline use of bottom liners by CCR landfills and surface impoundments from the 

following sources: 1) Impoundment data from EPA/OSWER’s 2009-2011 impoundment dam integrity 

site inspections; http://www.epa.gov/waste/nonhaz/industrial/special/fossil/surveys2/index.htm; 2) 

Impoundment data from ORCR’s 2009 Information Collection Request (ICR) addressing power plants 

with impoundments; http://www.epa.gov/waste/nonhaz/industrial/special/fossil/coalashletter.htm; and 3) 

Landfill and impoundment data from EPA Office of Water’s 2010 ICR addressing power plants to be 

affected by the Steam Electric Power Generating Effluent Guidelines: 

http://water.epa.gov/scitech/wastetech/guide/steam_index.cfm#point6.

225 See http://www.epa.gov/aboutepa/#regional for a list of states covered by each EPA Regional office. 

226 According to the Report to Congress I (1988), in the mid-1980s, the distribution of unlined CCR waste 

units across EPA regions was as follows: For surface impoundments: 31.7 percent (Region 4); 18.6

percent (Region 5); 6.2 percent (Region 7); and 3.5 percent (Region 3). For landfills: 11.1 percent 

(Region 5); 2.9 percent (Region 3); and 2.4 percent (Region 4).
Document submitted to conclude E.O.12866 Review

569

units associated with groundwater damage cases has further increased, due to the continued drop 

in power demand during the economic recession, which has resulted in power station temporary 

removal from active service (i.e., mothballing) and closures, combined with an increasing switch 

by many facilities to a more cost-effective fossil fuel (i.e., natural gas).

E. Conclusions

EPA now has a significantly better understanding of CCR damage cases than when the 

proposed rule was issued. First, damage cases are more numerous than previously contemplated 

and as more monitoring well systems are installed, the number of damage cases is likely to 

increase. Second, the CCR damage case record corroborates the findings of the risk analysis by 

demonstrating the greater vulnerability of groundwater (and surface water) to wet disposal (i.e., 

surface impoundments). Third, the damage cases show a direct correlation between the absence 

of liners and groundwater impacts, and illustrate that whereas in general the design of waste units 

– particularly surface impoundments – has improved over time, a notable portion of CCR 

impoundments constructed in the last two decades still lack a protective liner, thus presenting a 

potential threat to groundwater. Finally, a recent CCR spill incident227 demonstrates that inactive 

surface impoundments that have not been properly decommissioned (i.e., by breaching, 

dewatering, and capping or by clean-closing) continue to pose a significant risk to human health 

and the environment.

XII: Summary of Regulatory Impact Analysis

EPA estimated the costs and benefits of the final rule. The Regulatory Impact Analysis 

(RIA) is available to the public in the docket for today’s action. 

A. Costs of the Final Rule

 

227 The Duke Energy’s Dan River, North Carolina, February 2, 2014 CCR slurry spill.
Document submitted to conclude E.O.12866 Review

570

The estimated costs of the final rule are summarized in Exhibit XIII-A below. These are 

the incremental costs above the “baseline.” i.e., the current costs for managing CCR absent this 

regulation. The baseline takes into account existing state regulations for managing CCR now 

and into the future. To the extent that some states may have granted waivers or variances for 

certain provisions of State requirements, or in other instances may have added extra pollution 

control requirements above existing regulatory requirements to some specific permits issued to 

electric utility plants for operating CCR management units, the RIA did not take those actions 

into account. 

EPA used the following data sources to create a model for the RIA that estimates the 

costs and benefits of the rule: (1) 2012 DOE EIA-923 database; (2) ORCR’s 2009-2012 CCR 

impoundment site inspections; (3) impoundment data from ORCR’s 2009 mail survey to plants 

with CCR impoundments; (4) landfill and impoundment data from EPA Office of Water’s 2010 

mail survey to power plants in support of the 2013 proposed Steam Electric Power Generating 

Effluent Limitation Guidelines; (5) Integrated Planning Model (IPM) v. 5.13 (for the future 

projection of coal consumption by electric utility plants); and (6) the 1995 Electric Power 

Research Institute (EPRI) Co-management Survey.

Exhibit XII-A 

Estimated Cost of Pollution Controls Required by the CCR Final Rule (millions 2013$)

@ 3% Discount Rate @ 7% Discount Rate

CCR Pollution 

Control

Annualized 

Values

Present 

Values

Annualized 

Values

Present 

Values

1. Groundwater 

monitoring $4.79 $151 $2.80 $39.9

2. Bottom liners $491 $15,500 $297 $4,230

3. Leachate 

collection system 

(landfills only)

$51.6 $1,630 $18.4 $263

4. Fugitive CCR 

dust controls $7.09 $224 $3.36 $48.0
Document submitted to conclude E.O.12866 Review

571

5. Stormwater runon/run-off controls $18.8 $594 $13.0 $186

6. Location 

restrictions $43.6 $1,380 $20.0 $285

7. Closure capping $20.1 $630 $12.0 $171

8. Post-closure 

groundwater 

monitoring (30 

years)

$0.08 $2.40 $0.04 $0.61

9. Impoundment 

structural integrity 

requirements

$10.9 $344 $11.1 $158

10. Corrective action 

(CCR contaminated 

groundwater 

cleanup)

$19.0 $600 $19.1 $273

11. Reporting and 

recordkeeping $26.3 $831 $27.3 $389

12. Conversion to 

dry CCR handling $29.0 $916 $57.3 $818

Exhibit XII-A 

Estimated Cost of Pollution Controls Required by the CCR Final Rule (millions 2013$)

@ 3% Discount Rate @ 7% Discount Rate

CCR Pollution 

Control

Annualize

d Values

Present 

Values

Annualized 

Values

Present 

Values

13. Inactive 

impoundments 

(dewater and closure 

cap)

$12.0 $380 $26.7 $381

14. Subtotal industry 

costs (1+...+13) $734 $23,200 $508 $7,240

State Agency 

Burden Costs

15. Impoundment 

structural integrity 

requirements

$0.22 $6.88 $0.22 $3.16

16. Corrective action $0.38 $12.0 $0.38 $5.45

17. Reporting and 

recordkeeping $0.53 $16.6 $0.55 $7.78

18. Subtotal State 

agency burden costs 

(15+16+17)

$1.12 $35.5 $1.15 $16.4

19. Total cost 

(14+18) $735 $23,200 $509 $7,260
Document submitted to conclude E.O.12866 Review

572

B. Benefits of the Final Rule

The RIA contains two categories of benefits (1) benefits that are monetized and (2) nonmonetized benefits. The RIA estimates 11 categories of expected future human health and 

environmental benefits for the CCR rule. These include reduced future CCR impoundment 

structural failure releases; reduced future CCR groundwater contamination; improved air quality

from reduced power plant air pollution; and surface water quality benefits. The estimated value 

of each of the 11 monetized benefits is presented in Exhibit XIII-B below.
Document submitted to conclude E.O.12866 Review

573

Table XII-B

EPA Estimated Monetized Benefits for the CCR Final Rule

(millions 2013$ over 100-year period of analysis 2016-2114)

3% discount rate 7% discount rate

Annualized Present 

Value Annualized Present Value

1. Reduced 

CCR 

impoundment 

structural 

failure releases 

$151 $4,760 $138 $1,960

2. Reduced 

CCR landfill & 

impoundment 

groundwater 

contamination

$12.8 $405 $9.86 $141 

3. Induced 

increase in 

future annual 

CCR beneficial 

uses 

$117 $3,130 $79.0 $1,120 

4. Reduced 

incidence of 

cancer from 

CCR exposure

< $0.1 $0.17 < $0.1 < $0.1 

5. Avoided IQ 

losses from 

mercury in 

CCR

$0.28 $8.80 < $0.1 $0.35 

6. Avoided IQ 

losses from lead

in CCR

$0.186 $5.87 < $0.1 $0.23 

7. Reduced 

need for 

specialized 

education

(associated with 

5 & 6 above)

< $0.1 < $0.1 < $0.1 < $0.1 

8. Non-market 

surface water 

quality benefits

$2.26 $71.4 $1.89 $27.0 

9. Protection of 

threatened & 

endangered 

species near 

$0.91 $28.7 $0.76 $10.8 
Document submitted to conclude E.O.12866 Review

574

CCR 

impoundments
Document submitted to conclude E.O.12866 Review

575

Table XII-B

EPA Estimated Monetized Benefits for the CCR Final Rule

(millions 2013$ over 100-year period of analysis 2016-2114)

3% discount rate 7% discount rate

Annualized Present 

Value Annualized Present Value

10. Improved 

air quality from 

induced 

changes to 

power plant 

emissions

$4.66 $147 $2.04 $29.1 

11. Reduced 

power plant 

groundwater 

withdrawals

< $0.1 < $0.1 < $0.1 < $0.1

12 Total 

monetized 

benefits (1 

+...+ 11)

$289 $8,550 $232 $3,290

In addition to the monetized benefit categories, the RIA describes 11 additional nonmonetized benefit categories. Due to uncertainties and weaknesses in supporting documentation 

for quantifying and monetizing these benefits, the RIA presents these benefits separately from 

the benefits listed above, and does not include them in the quantified comparison of benefits and 

costs. These non-monetized benefits include:

1. Financial market benefits

2. Reduced community dread of CCR impoundment structural failure releases

3. Reduced health and property nuisance impacts from CCR fugitive dust 

4. Cancer and non-cancer human health benefits from reduced CCR contamination of fish 

consumed by recreational anglers and subsistence fisher households in surface waters 

near power plants (additional to monetized avoided health effects)
Document submitted to conclude E.O.12866 Review

576

5. Cancer and non-cancer human health benefits from reduced CCR exposure by other 

recreational users of surface waters near power plants (additional to monetized avoided 

health effects)

6. Avoided CCR contamination of sediments in surface waters near power plants

7. Water quality benefits from avoided CCR contamination treatment costs for use of 

surface waters for drinking and irrigation water supply

8. Commercial fisheries benefit in surface waters near power plants

9. Increased participation in water-based recreation near power plants

10. Avoided fish impingement and entrainment mortality from power plant water intakes

(induced conversion to dry CCR handling reduces future water demand for CCR sluicing)

11. Increased property values surrounding electric utility plants (from closure capping and revegetation of CCR surface impoundments)

The total monetized benefits less the total costs of the rule provide the net monetized 

benefits of the rule. Exhibit XIII-C summarizes the total costs and benefits as well as the net 

benefits of the rule. 

Exhibit XII-C

EPA Estimated Incremental Costs & Benefits of the CCR Rule

(millions 2013$ over 100-year period of analysis 2015-2114)

3% 

discount rate

7% 

discount rate

A. Annualized Values

A1. Total Costs $735 $509

A2 Total monetized 

benefits $289 $232

A3. Net Benefits (A2 - A1) ($446) ($277)

A4. Benefit to Cost Ratio 

(A3 / A1) 0.39 0.46

B. Present Value

B1. Total Costs $23,200 $7,260

B2 Total monetized 

benefits $8,550 $3,290

B3. Net Benefits (B2 - B1) ($14,650) ($3,970)
Document submitted to conclude E.O.12866 Review

577

Exhibit XII-C

EPA Estimated Incremental Costs & Benefits of the CCR Rule

(millions 2013$ over 100-year period of analysis 2015-2114)

B4. Benefit to Cost Ratio 

(B2/ B1) 0.37 0.45

XIII. Uniquely Associated Wastes

By way of this rule, EPA is codifying in § 261.4(b) (4) a list of low volume waste that 

when co-disposed with CCR are not subject to hazardous waste regulations. These wastes are 

also referred to as uniquely associated wastes. However, these uniquely associated wastes are 

subject to hazardous waste regulations when they are not co-disposed with CCR. 

In a letter to EPA dated October 10, 1980 the Utility Solid Waste Activities Group 

(USWAG) suggested interpretive language that EPA should adopt regarding the amendments to 

the Solid Waste Disposal Act Amendments of 1980 which address fossil fuel combustion wastes. 

EPA replied to USWAG by letter dated January 13, 1981 (known as the 1981 Dietrich letter), 

and addressed, among other issues, other associated wastes generated in conjunction with the 

burning of fossil fuels.228 EPA stated that “We believe it is appropriate, in the light of 

Congressional intent, to interpret the §261.4(b) (4) exclusion to include other wastes that are 

generated in conjunction with the burning of fossil fuels and mixed with and co-disposed or cotreated with fly ash, bottom ash, boiler slag and flue gas emission control wastes.” When 

amendments to the 1980 Solid Waste Disposal Act were introduced, Congressmen Bevill and 

Rahall stated, respectively:

“It is the sponsor's intention that this list of waste materials in the amendment be read 

broadly, to incorporate the waste products generated in the real world as a result of the 

 

228

 See letter from Gary N. Dietrich to Paul Elmer, USWAG, available in the docket for this rule.
Document submitted to conclude E.O.12866 Review

578

combustion of fossil fuels. We do not believe that these terms should be narrowly read and thus 

impose regulatory burdens upon those who seek to assist the Nation by burning coal. EPA 

should recognize that these "waste streams" often include not only the byproducts of the 

combustion of coal and other fossil fuels, but also relatively small proportions of other materials 

produced in conjunction with the combustion, even if not derived directly from these fuels. EPA 

should not regulate these waste streams because of the presence of these materials, if there is no 

evidence of any substantial environmental danger from these mixtures.” (126 Cong. Rec. 

H1102).

“In the real world, these waste materials do not include solely fly ash, bottom ash, slag, or 

scrubber sludge. Quite often, other materials are mixed with these large volume waste streams, 

with no environmentally harmful effects, and often with considerable benefit-as when, for 

example, boiler cleaning- acids are neutralized by being mixed with alkaline fly ash. These 

appear to me to be environmentally beneficial practices, which EPA should encourage. At the 

very least, however, the Agency should take no steps to discourage them until it has developed a 

full factual understanding of the situation. This amendment would assure that EPA allows all 

persons burning coal to avoid unnecessary regulation of the byproducts produced by that 

combustion, as those byproducts are currently being managed in the real world, by real people, 

with real sense.” (126 Cong. Rec. H1104).

As such, EPA interpreted 40 CFR §261.4(b) (4) (the Bevill exemption) to mean that 

wastes produced in conjunction with the combustion of fossil fuels, which are necessarily 

associated with the production of energy, and which traditionally have been, and which actually 

are, mixed with and co-disposed or co-treated with fly ash, bottom ash, boiler slag, or flue gas 

emission control wastes from coal combustion are not hazardous wastes. In the Deitrich letter 
Document submitted to conclude E.O.12866 Review

579

EPA stated that these other associated wastes include, but are not limited to the following wastes: 

(1) boiler cleaning solutions; (2) boiler blowdown; (3) demineralizer regenerant; (4) pyrites; and 

(5) cooling tower blowdown.

In a February 1988 Report to Congress on Wastes from the Combustion of Coal by 

Electric Utility Power Plants EPA listed the following low-volume wastes commonly produced 

in conjunction with the burning of fossil fuels to produce electricity: (1) boiler blowdown; (2) 

coal pile runoff; (3) cooling tower blowdown; (4) demineralizer regenerants and rinses; (5) metal 

and boiler cleaning wastes; (6) pyrites; and (7) sump effluents. Presented for each type of lowvolume waste is a brief description of how the waste is generated, typical quantities produced, 

and the physical and chemical composition of the waste.229 The source of this information was 

primarily an August 1981 USWAG/Edison Electric Institute report in response to a request for 

information in the 1981 Dietrich letter.

In an August 1, 1993 Regulatory Determination the Agency emphasized that comanagement of low-volume wastes and large-volume wastes (fly ash, bottom ash, boiler slag, or 

flue gas emission control wastes from coal combustion) makes the combined waste stream a 

remaining waste that would be subject to a subsequent Regulatory Determination and provided 

the list below of management practices that result in combined waste streams that are remaining 

wastes.230

 Discharge of boiler blowdown to a large-volume waste impoundment, 

 Discharge of demineralizer regenerant to a large-volume waste impoundment, 

 

229

 See http://www.epa.gov/osw/nonhaz/industrial/special/fossil/coal-rtc.pdf, pages 3-41 to 3-62. This 

report addressed wastes generated from the combustion of coal by electric utility power plants, and did 

not address comanaged utility coal combustion wastes, other fossil fuel combustion wastes, and wastes 

from non-utility boilers.

230

 http://www.epa.gov/osw/nonhaz/industrial/special/mineral/080993.pdf
Document submitted to conclude E.O.12866 Review

580

 Discharge of metal cleaning wastes to a large-volume waste impoundment, 

 Discharge of boiler chemical cleaning wastes to a large-volume waste impoundment, 

 Discharge of plant wastewater treatment effluent to a large-volume waste impoundment, 

 Discharge of coal mill rejects to a large-volume waste impoundment,

 Disposal of oil ash in a large-volume waste landfill or impoundment, 

 Disposal of plant wastewater treatment sludge in a large-volume waste landfill.

In a 1999 Report to Congress on wastes from the combustion of fossil fuels231 EPA stated 

that low-volume wastes are generated as a result of supporting processes that are ancillary to, but 

a necessary part of, the combustion and power generation processes and provided the following 

list of low-volume wastes.

• Coal pile runoff. 

• Coal mill rejects/pyrites. 

• Boiler blowdown. 

• Cooling tower blowdown and sludge. 

• Water treatment sludge. 

• Regeneration waste streams. 

• Air heater and precipitator washwater. 

• Boiler chemical cleaning waste. 

• Floor and yard drains and sumps. 

• Laboratory wastes. 

• Wastewater treatment sludge. 

 

231

 http://www.epa.gov/osw/nonhaz/industrial/special/fossil/volume_2.pdf
Document submitted to conclude E.O.12866 Review

581

The concept of uniquely associated wastes with respect to CCR was first introduced in 

the May 22, 2000 Regulatory Determination. Prior to this, these wastes were referred to as other 

wastes, remaining wastes, or low-volume wastes, that are generated in conjunction with the 

burning of fossil fuels and mixed with and co-disposed or co-treated with fly ash, bottom ash, 

boiler slag and flue gas emission control wastes. For the May 22, 2000 Regulatory 

determination, the Agency proposed the uniquely associated wastes concept with the intent of 

being consistent with other wastes covered under the Bevill Amendment (a.k.a., the Bevill 

exemption), such as mining and mineral processing wastes that the Agency refers to as uniquely 

associated wastes, and under the Bentsen Amendment for oil and gas exploration and production 

wastes which are referred to as associated wastes. The Agency recognized that determining 

whether a particular waste is uniquely associated with fossil fuel combustion involves an 

evaluation of the specific facts of each case. In the Agency’s view, the following qualitative 

criteria should be used to make such determinations on a case-by-case basis:

(1) Wastes from ancillary operations are not ‘‘uniquely associated’’ because they are not 

properly viewed as being ‘‘from’’ fossil fuel combustion.

(2) In evaluating a waste from non-ancillary operations, one must consider the extent to 

which the waste originates or derives from the fossil fuels, the combustion process, or 

combustion residuals, and the extent to which these operations impart chemical characteristics to 

the waste.

EPA proposed the following list of wastes that the Agency considered to be uniquely 

associated wastes (i.e., uniquely associated with the combustion of coal for the generation of 

electricity at electric utilizes and independent power producers and, therefore, covered by the 

Bevill exemption).
Document submitted to conclude E.O.12866 Review

582

 Coal Pile Runoff

 Coal Mill Rejects and Waste Coal

 Air Heater and Precipitator Washes

 Floor and Yard Drains and Sumps

 Wastewater Treatment Sludges

 Boiler Fireside Chemical Cleaning Wastes

EPA also proposed the following list of wastes that would not be considered uniquely 

associated wastes. 

 Boiler Blowdown

 Cooling Tower Blowdown and Sludges

 Intake or Makeup Water Treatment and Regeneration Wastes

 Boiler Waterside Cleaning Wastes

 Laboratory Wastes

 General Construction and Demolition Debris

 General Maintenance Wastes 

EPA requested comments on these proposed lists and received several comments from 

states, industry, and the environmental community. Industry opposed the “uniquely associated” 

waste framework, and favors retaining the 1981"Dietrich Policy." 

Many commenters argued that the Dietrich policy has provided clear guidance on the 

scope of the Bevill exemption for the past 20 years, and that appropriate waste management 

practices have been implemented for these wastes. The Dietrich Policy has proven itself 

effective in furthering congressional intent to recognize certain historic co-management practices 

provided they are not environmentally harmful. The Association of State and Territorial Solid 
Document submitted to conclude E.O.12866 Review

583

Waste Management Officials recommended that EPA contact States that have management

programs for fossil fuel combustion wastes to determine how to best manage the waste that are 

uniquely associated or not uniquely associated with fossil fuel combustion wastes. The Hoosier 

Environmental Council opposed exempting coal wastes and stated that "coal mill rejects and coal 

pile runoff would not be uniquely associated wastes ... because neither of these wastes is derived 

from coal combustion."

EPA acknowledges that the Deitrich letter has been longstanding policy with regard to 

CCR uniquely associated wastes and that the Agency has not sought input from States on the 

issue. Moreover, as evident from the Congressional Record, the Congressional intent was to 

“include not only the byproducts of the combustion of coal and other fossil fuels, but also 

relatively small proportions of other materials produced in conjunction with the combustion, 

even if not derived directly from these fuels.” These other materials would include many of 

those listed in the Dietrich letter as well as many of those listed in the May 2000 Regulatory 

determination.

After considering the 1981 Dietrich letter, a copy of which is included in the docket for 

this rule, the proposed guidance in the May 2000 Regulatory Determination, comments received 

on the May 2000 Regulatory Determination and the July 2010 proposed rule, EPA has concluded 

that the 1981 Dietrich letter accurately reflects the intent of Congress when they exempted CCR 

from hazardous waste regulations. EPA also believes that many of the wastes listed as uniquely 

associated wastes in the May 22, 2000 Regulatory Determination are also consistent with the 

Congressional intent. Therefore, the Agency is finalizing the following list of uniquely 

associated wastes that includes materials from both the Dietrich letter and the May 2000 

Regulatory Determination. 
Document submitted to conclude E.O.12866 Review

584

 Coal pile run-off

 Boiler cleaning solutions,

 Boiler blowdown,

 Process water treatment and demineralizer regeneration wastes, 

 Cooling tower blowdown,

 Air heater and precipitator washes,

 Effluents from floor and yard drains and sumps, and

 Wastewater treatment sludges. 

This list is being codified in 40 CFR part 261.4(b): Solid wastes which are not hazardous 

wastes.

XIV. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review and Executive Order 13563: 

Improving Regulation and Regulatory Review 

Under section 3(f)(1) of Executive Order 12866 (58 FR 51735, October 4, 1993), this 

action is an "economically significant regulatory action” because it is likely to have an annual 

effect on the economy of $100 million or more. The total annual cost of this final rule is 

estimated to be $509 million a year using a 7% discount rate. Accordingly, EPA submitted this 

action to the Office of Management and Budget (OMB) for review under Executive Orders 

12866 and 13563 (76 FR 3821, January 21, 2011) and any changes made in response to OMB 

recommendations have been documented in the docket for this action.

In addition, EPA prepared an analysis of the potential costs and benefits associated with 

this action. The Regulatory Impact Analysis (RIA) estimated the costs and benefits for this

action. The RIA estimated 12 regulatory costs: (1) groundwater monitoring; (2) bottom liner 
Document submitted to conclude E.O.12866 Review

585

installation; (3) leachate collection system installation and management; (4) fugitive dust 

controls; (5) rain and surface water run-on/run-off controls; (6) disposal unit location restrictions 

(including water tables, floodplains, wetlands, fault areas, seismic zones, and karst terrain); (7) 

closure capping to cover units; (8) post-closure groundwater monitoring requirements; and (9) 

impoundment structural integrity requirements; (10) corrective actions (CCR contaminated 

groundwater cleanup); (11) paperwork reporting/recordkeeping; and (12) impoundment closures 

and conversion to dry handling. Using a 7% discount rate, the annualized costs are estimated at 

$509 million, and using a 3% discount rate, annualized costs are estimated to be $735 million. 

Using a 7% discount rate, the total present value costs are estimated at $7.3 billion, and using a 

3% discount rate the present value of estimated costs is $23.2 billion. 

The RIA estimated 11 monetized benefits: (1) CCR impoundment release prevention; (2)

CCR landfill & impoundment groundwater contamination prevention; (3) induced increase in 

CCR beneficial uses (e.g., concrete, wallboard); (4) reduced incidence of cancer from CCR 

exposure; (5) avoided IQ losses from mercury; (6) avoided IQ losses from lead; (7) reduced need 

for specialized education; (8) non-market surface water quality benefits; (9) protection of 

threatened & endangered species near CCR impoundments; (10) improved air quality from 

induced changes to power plant emissions and (11) reduced power plant groundwater 

withdrawals. The annualized monetized benefits are estimated at $289 million (@ 3% discount 

rate) and $232 million (@ 7% discount rate). The total present value monetized benefits are 

estimated at $8.6 billion (@ 3% discount rate) and $3.3 billion (@ 7% discount rate).

B. Paperwork Reduction Act (PRA)

The information collection activities in this rule will be submitted for approval to the 

Office of Management and Budget (OMB) under the PRA. The Information Collection Request 
Document submitted to conclude E.O.12866 Review

586

(ICR) document that the EPA prepared has been assigned EPA ICR number 1189.25, OMB 

control number 2050-0053. You can find a copy of the ICR in the docket for this rule, which will 

be available in the docket once the ICR has been submitted to OMB for review, and it is briefly 

summarized here. The information collection requirements are not enforceable until OMB 

approves them.

These regulations, promulgated under subtitle D of RCRA, constitute national minimum 

criteria with which facilities must comply without oversight or intervention by a federal or state 

authority. To address concerns about the absence of regulatory oversight under a subtitle D 

regulation, EPA has developed a combination of mechanisms, including recordkeeping, 

notification, and maintaining a publicly accessible internet site. The increased transparency 

resulting from these requirements will minimize the potential for owners or operators to abuse 

the self-implementing system established in this rule. In addition, these requirements provide 

interested parties the information necessary to determine whether the owner or operator is 

operating in compliance with the requirements of the rule and thus will facilitate enforcement by 

States and private citizens. EPA has consolidated the recordkeeping, notification, and internet 

posting requirements into a single section of the regulations in an effort to make these 

requirements easier to follow. It is important to note that EPA will not be collecting any 

information under this rule-instead, facilities must keep records, notify the state, and post 

information on a publicly available website. EPA has taken steps to minimize the burden to the 

regulated community while at the same time achieving the transparency needed to ensure proper 

implementation of this rule. In addition to the burden to owner and operators of CCR landfills, 

in an effort to ease implementation, EPA has reporting and record keeping requirements for 

certain beneficial uses and States. For beneficial use that meets the fourth criteria, the user must 
Document submitted to conclude E.O.12866 Review

587

maintain records and provide documentation upon request. For States, States are encouraged to 

voluntarily adopt at least the federal minimum criteria through the revision of SWMPs. In 

addition, EPA estimated the burden on state government agencies associated with the receipt of 

various notification requirements in the rule. 

The respondents/affected entities are the owners/operators of electric utilities and 

independent power producers that fall within the NAICS code 221112. Specifically, these 

regulations apply to owners and operators of new and existing landfills and new and existing 

surface impoundments, including lateral expansions that of all landfills and surface 

impoundments that dispose or otherwise engage in solid waste management of CCR generated 

from the combustion of coal at electric utilities. The rule also applies to CCR units located offsite of the electric utilities’ or independent power producers’ facilities that receive CCR for 

disposal. The rule applies to certain inactive CCR surface impoundments at active electric 

utilities’ or independent power producers’ facilities, if the CCR unit still contains CCR and 

liquids. Finally, the rule applies to certain beneficial users of CCR. The rule may also impact 

States that choose to revise their SWMPs. 

Respondents are obligated to keep records, make the required notifications, and maintain 

the publicly available internet site. These requirements are part of the minimum federal criteria 

under 40 CFR Part 257 and promulgated under the authority of sections 1006(b), 1008(a), 

2002(a), 3001, 4004, and 4005(a) of the Solid Waste Disposal Act of 1970, as amended by the 

Resource Conservation and Recovery Act of 1976 (RCRA), as amended by the Hazardous and 

Solid Waste Amendments of 1984 (HAS), 42 U.S.C 6906(b), 6907(a), 6912(a), 6944, and 

6945(a). 
Document submitted to conclude E.O.12866 Review

588

Respondents/affected entities: EPA estimates the total number of respondents to be 486. 

This number represents the estimated number of coal-fired electric utility plants that will be 

affected by the rule. 

Respondent’s obligation to respond: The recordkeeping, notification, and posting are part 

of the minimum national criteria being promulgated under Sections 1008, 4004, and 4005(a) of 

RCRA.

Estimated number of respondents: 486. 

Frequency of response: The frequency of response varies. 

Total estimated burden: EPA estimates the total annual burden to respondents to be 

approximately 288,880 hours with a three year total estimated burden of 866,640 hours. Burden 

is defined at 5 CFR 1320.3(b).

Total estimated cost: The total estimated annual cost is approximately $51,768,757; this 

is composed of approximately $18,374,757 in annualized labor costs and $33,394,000 in 

annualized capital or operation and maintenance costs. The three year total estimated costs are

$155,306,271 composed of $55,124,271 in labor costs and 100,182,000 in operations and 

maintenance.

In addition, developing a state SWMP (see Unit IX of this preamble) is not a requirement 

under this rule, however, EPA is encouraging states to develop these plans and has developed a 

burden estimate associated with this activity. The estimate for this one-time activity has been 

annualized over the three-year period covered by the ICR. The total estimated annual burden 

(for the 47 states and Puerto Rico where CCR are generated) is approximately 10,880 hours, and 

approximately $429,414 in annualized labor costs; this estimate assumes no annualized capital or 

operations and maintenance costs.
Document submitted to conclude E.O.12866 Review

589

An agency may not conduct or sponsor, and a person is not required to respond to, a 

collection of information unless it displays a currently valid OMB control number. The OMB 

control numbers for the EPA’s regulations in 40 CFR are listed in 40 CFR part 9. When OMB 

approves this ICR, the Agency will announce that approval in the Federal Register and publish a 

technical amendment to 40 CFR part 9 to display the OMB control number for the approved 

information collection activities contained in this final rule.

C. Regulatory Flexibility Act

The Regulatory Flexibility Act (RFA) generally requires an agency to prepare a 

regulatory flexibility analysis of any rule subject to notice and comment rulemaking 

requirements under the Administrative Procedure Act or any other statute unless the agency 

certifies that the rule will not have a significant economic impact on a substantial number of 

small entities (SISNOSE). Small entities include small businesses, small organizations, and 

small governmental jurisdictions.

For purposes of assessing the impacts of this rule on small entities, small entity is defined 

as: (1) a small business, based on the U.S. Small Business size standard for NAICS code 221112 

(fossil fuel electric utility plants), with fewer than 750 employees; (2) a small government 

jurisdiction, based on the RFA/SBREFA’s definition (5 U.S. Code section 601(5)), is the 

government of a city, county, town, township, village, school district, or special district with 

population under 50,000; (3) a small organization that is any not-for-profit enterprise which is 

independently owned and operated and is not dominant in its field.

After considering the economic impacts of this final rule on small entities, I certify that 

this action will not have a significant economic impact on a substantial number of small entities.
Document submitted to conclude E.O.12866 Review

590

The small entities directly regulated by this final rule consist of one small county, 31 

small cities, 32 small companies, and 13 small cooperative owner entities that own at least one 

coal-burning power plant. There are 91 coal-burning power plants that are owned by the 77 small 

owner entities. Those plants fall into the following categories: one small county plant, 31 small 

city plants, 42 plants owned by small companies, and 17 small cooperative plants.

The RIA estimated CCR compliance costs as a percentage of revenues for each entity and 

found that for almost all small entities affected by the rule the estimated annualized costs were 

less than 1% of revenues. 

Although this final rule will not have a significant economic impact on a substantial 

number of small entities, EPA nonetheless has tried to reduce the impact of this rule on small 

entities. 

D. Unfunded Mandates Reform Act (UMRA)

Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), 2 U.S.C. 1531-1538, 

requires Federal agencies, unless otherwise prohibited by law, to assess the effects of their 

regulatory actions on State, local, and tribal governments and the private sector. This rule 

contains a Federal mandate that may result in expenditures of $100 million or more for State, 

local, and tribal governments, in the aggregate, or the private sector in any one year. 

Accordingly, EPA has prepared under section 202 of the UMRA a written statement which is 

summarized below.

The RIA estimates the rule may affect 414 coal-fired electric utility plants, and may have 

a nationwide average annualized cost of approximately $509 million per year (at a 7% discount 

rate). Of this amount, average annualized costs to State/local governments total $36 million, and 

the average annualized cost to the private sector totals approximately $436 million per year (the 
Document submitted to conclude E.O.12866 Review

591

remainder of the total costs are the costs associated with compliance at federally-owned electric 

utility plants.)

Consistent with the intergovernmental consultation provisions of section 204 of the 

UMRA, EPA initiated pre-proposal consultations with governmental entities affected by this 

rule. In developing the regulatory options for the CCR rule, EPA consulted with small 

governments according to EPA’s UMRA interim small government consultation plan developed 

pursuant to section 203 of UMRA. EPA’s interim plan provides for two types of possible small 

government input: technical input and administrative input. According to this plan, and 

consistent with section 204 of UMRA, early in EPA’s 2009 process for developing the CCR rule, 

EPA implemented a small government consultation process consisting of two consultation 

components: (1) a series of meetings in 2009 for purposes of acquiring technical input from State 

government officials, and (2) letters to 10 organizations representing elected State and local 

government officials to inform and seek input for the rule’s development, as well as to invite 

them to a meeting held September 16, 2009 in Washington DC to provide input on the rule. 

Following are the meetings held with State officials in 2009: (1) February 27 with the 

Association of State and Territorial Solid Waste Management Officials (ASTSWMO) Coal Ash 

Workgroup (Washington DC), (2) March 22-24 with the Environmental Council of States 

(ECOS) Spring Meeting (Alexandria VA), (3) April 15-16 with the ASTSWMO Mid-Year 

Meeting (Columbus OH), (4) May 12-13 with the EPA Region IV State Directors Meeting 

(Atlanta, GA), (5) June 17-18 with the ASTSWMO Solid Waste Managers Conference (New 

Orleans, LA), (6) July 21-23 with the ASTSWMO Board of Directors Meeting (Seattle, WA), 

and (7) August 12 with the ASTSWMO Hazardous Waste Subcommittee Meeting (Washington 

DC). ASTSWMO is an organization with a mission to work closely with the EPA to ensure that 
Document submitted to conclude E.O.12866 Review

592

its State government members are aware of the most current developments related to State waste 

management programs. ECOS is a national non-profit, non-partisan association of State and 

territorial environmental agency leaders. As a result of these meetings EPA received letters in 

mid-2009 from 22 State governments as well as a letter from ASTSWMO expressing their stance 

on CCR regulatory options.

On August 24, 2009 letters were mailed to the following 10 organizations, which include 

representation from small government elected officials, to inform and seek input for the rule 

development, as well as to invite them to a meeting held September 16, 2009 in Washington DC: 

(1) National Governors Association, (2) National Conference of State Legislatures, (3) Council 

of State Governments, (4) National League of Cities, (5) U.S. Conference of Mayors, (6) County 

Executives of America, (7) National Association of Counties, (8) International City/County 

Management Association, (9) National Association of Towns and Townships, and (10) 

Environmental Council of the States. These 10 organizations representing State and local 

government officials are identified in EPA’s November 2008 Federalism guidance as the “Big 

10” organizations appropriate to contact for purpose of consultation with small government 

elected officials. 

Consistent with section 205, EPA identified and considered a reasonable number of 

regulatory alternatives in the June 2010 proposed rule, and is adopting the least-costly approach 

(i.e. a modified version of the “D Prime” least costly approach presented in the 2010 proposed 

CCR rule). 

This rule is not subject to the requirements of section 203 of UMRA because it contains 

no regulatory requirements that might significantly or uniquely affect small governments. The 

threshold amount established for determining whether regulatory requirements could 
Document submitted to conclude E.O.12866 Review

593

significantly affect small governments is $100 million annually. The RIA estimates a $1.2 

million annual cost for State/local government implementation of the rule and $36 million in 

annual direct compliance costs on 57 State or local governments. These estimates are well below 

the $100 million annual threshold established under UMRA. However this rule does have over a 

$100 million dollar impact on industry. EPA selected one of the lower industry cost options for 

the final rule by selecting a RCRA Subtitle D rule instead of a RCRA Subtitle C rule.

E. Executive Order 13132 - Federalism

The EPA has concluded that this action may have federalism implications because it 

imposes substantial direct compliance costs on State or local governments, and the Federal 

government will not provide the funds necessary to pay those costs. Based on the estimates in 

EPA’s RIA for this action, the final rule, if promulgated, may impose a $1.2 million annual cost 

for State/local government implementation of the rule and $36 million in annual direct 

compliance costs on 57 State or local governments. This amount exceeds the $25 million per 

year “substantial compliance cost” threshold defined in section 1.2(A) (1) of EPA’s November 

2008 “Guidance on Executive Order 13132: Federalism.” There are 57 State and local 

governments which own 68 coal-burning power plants or 16% of the 414 electric utility plants 

expected to be affected by this rule. These 57 local governments consist of 7 State governments, 

31 small municipality governments, 18 non-small municipal governments and 1 (small) county 

government owner.

The EPA provides the following federalism summary impact statement. The EPA 

consulted with State and local officials early in the process of developing the proposed action to 

permit them to have meaningful and timely input into its development. In developing the

regulatory options described in this final action, EPA consulted with 10 national organizations 
Document submitted to conclude E.O.12866 Review

594

representing State and local elected officials to ensure meaningful and timely input by State/ 

local governments, consisting of two consultation components. This consultation is described 

and summarized in the UMRA section above. 

In the spirit of Executive Order 13132, and consistent with EPA policy to promote 

communications between EPA and State and local governments, EPA specifically solicited 

comment on the proposed action from State and local officials. EPA received comments from 

over two hundred (200) entities representing State and local governments. The comments 

submitted primarily addressed the issue presented in the proposal of which approach to 

regulating CCR was appropriate – a regulation under subtitle C or under subtitle D of RCRA. 

The State and local government commenters overwhelming voiced their opposition to a 

regulation under subtitle C, citing impacts to State programs if EPA were to bring such a large 

number of facilities and a large volume of waste into the subtitle C universe. State governments 

were very concerned with the resources which would be required to issue subtitle C permits to 

these facilities and to develop and obtain EPA approval of revisions to their authorized RCRA 

subtitle C programs. They also expressed concerns about the limits in the existing hazardous 

waste disposal capacity in the United States to absorb such a large volume of new wastes, also 

citing the financial burden and potential liability problems for cities and towns that operate 

landfills or use landfills to dispose of waste that might include coal ash.

In addition, States and local governments expressed concern that a subtitle C rule would 

have a negative effect on beneficial use of CCR and on State beneficial use programs. State and 

local governments fully supported continued beneficial use of CCR and continuation of the 

Bevill exemption for CCR beneficial use. They requested that EPA establish standards to ensure 

that beneficial uses are protective of human health and the environment and ensure consistency 
Document submitted to conclude E.O.12866 Review

595

in management of these materials throughout the country. They specifically cited the use of CCR 

in cement and concrete applications, highway construction projects and wallboard manufacture 

(among other uses) and the impacts to municipalities through increased costs and potential job 

loss if CCR is classified as a hazardous waste. They also noted an expectation that utility rates 

would rise as a result of CCR being disposed of in landfills rather than being used for beneficial 

purposes, due to limited availability of commercial hazardous waste disposal facilities and costs 

of transporting high volumes of CCR to these facilities. State Departments of Transportation 

expressed particular concern that a subtitle C rule would negatively affect the use of CCR in road 

bed. Commenters further supported continued beneficial use of CCR to reduce the need for 

mining for substitute products in cement and concrete. Finally, should CCR be classified as a 

hazardous waste, they indicated the need for EPA to clarify that products made using CCR are 

new products and not considered hazardous wastes, and may be treated in the same manner as 

similar products made without CCR. 

Since EPA is promulgating this regulation under subtitle D, the concerns over the 

potential effect of a subtitle C regulation on beneficial use are moot. Moreover in this final rule, 

EPA has established a definition for beneficial use which we believe makes clear the distinction 

between beneficial use and disposal. This is fully discussed in unit VI of this notice.

While States supported a rule under Subtitle D, they also voiced concern about the need 

for flexibility to address site-specific situations, as would be available under a state permitting 

program, and concern about potential inconsistencies between the new federal requirements and 

existing State programs. States suggested that regulation under Subtitle D should embrace the 

existing state permitting programs−allowing state permitting programs as the foundation for 

regulating CCR disposal−and requested financial incentives to implement federal criteria through 
Document submitted to conclude E.O.12866 Review

596

state solid waste programs. They also emphasized the need to allow time for states to make 

necessary changes in existing state rules and statutes to incorporate federal criteria. A few 

expressed the desire that financial assurance for closure, post closure care, and corrective action 

should be included in the final rule as a mechanism to ensure that funds will be provided by 

owners and operators to carry out these activities. 

As fully explained earlier in this notice, EPA is promulgating this rule under subtitle D of 

RCRA. As such, these regulations constitute the minimum federal requirements which apply to 

CCR disposal units. States are not required to adopt these regulations or to revise their state 

programs to incorporate the new federal requirements. As fully discussed in Unit V, 

“Development of the RCRA Subtitle D Regulatory Approach,” sections 1008(a), 4004, and 

4005(a) of RCRA (i.e., subtitle D) does not provide EPA with the ability to require states to issue 

permits, to approve state programs to operate in lieu of the Federal Program, or to enforce any of 

the requirements addressing the disposal of CCR. Consequently EPA designed the final rule to 

ensure protection of public health and the environment within these limitations. In addition, to 

help address potential implementation challenges that this statutory and resulting regulatory 

structure impose, as fully set out in Section IX of this notice, EPA is encouraging States to revise 

their Solid Waste Management Plans and to submit these to EPA for approval. 

A complete list of the comments from State and local governments has been provided to 

the Office of Management and Budget and has been placed in the docket for this rulemaking. In 

addition, the detailed response to comments from these entities is contained in EPA’s response to 

comments document on this rulemaking. 

As required by section 8(a) of Executive Order 13132, EPA included a certification from 

its Federalism Official stating that EPA had met the Executive Order’s requirements in a 
Document submitted to conclude E.O.12866 Review

597

meaningful and timely manner when it sent the draft of this final action to OMB for review 

pursuant to Executive Order 12866. A copy of this certification is included in the public version 

of the official record for this final action.

F. Executive Order 13175 – Consultation and Coordination with Indian Tribal 

Governments

Subject to the Executive Order 13175 (65 FR 67249, November 9, 2000) EPA may not 

issue a regulation that has tribal implications, that imposes substantial direct compliance costs, 

and that is not required by statute, unless the Federal government provides the funds necessary to 

pay the direct compliance costs incurred by tribal governments, or EPA consults with tribal 

officials early in the process of developing the proposed regulation and develops a tribal 

summary impact statement. 

EPA has concluded that this action may have tribal implications. However, it will neither 

impose substantial direct compliance costs on tribal governments, nor preempt Tribal law. As 

identified in EPA’s Regulatory Impact Analysis for this action, there are no known tribal owner

entities of the coal-fired electric utility plants affected by this action. Although there are three of 

the 414 coal-fired electric utility plants (in operation as of 2012) which are located on tribal 

lands, they are not owned by tribal governments. These are: (1) Navajo Generating Station in 

Coconino County, owned by the Arizona Salt River Project; (2) Bonanza Power Plant in Uintah 

County, Utah, owned by the Deseret Generation and Transmission Cooperative; and (3) Four 

Corners Power Plant in San Juan County, New Mexico owned by the Arizona Public Service 

Company. The Navajo Generating Station and the Four Corners Power Plant are on lands 

belonging to the Navajo Nation, while the Bonanza Power Plant is located on the Uintah and 

Ouray Reservation of the Ute Indian Tribe.
Document submitted to conclude E.O.12866 Review

598

EPA consulted with tribal officials early in the process of developing this regulation to 

permit them to have meaningful and timely input into its development.

G. Executive Order 13045: Protection of Children from Environmental Health Risks and Safety 

Risks

This action is subject to EO 13045 (62 FR 19885, April 23, 1997) because it is an 

economically significant regulatory action as defined by EO 12866, and EPA believes that the 

environmental health or safety risks addressed by this action may have a disproportionate effect 

on children. Accordingly, we have evaluated the environmental health or safety effects of Coal 

Combustion Residual constituents of potential concern on children. The results of this evaluation 

are contained in the Human and Ecological Risk Assessment of Coal Combustion Wastes

available in the docket for this action.

As ordered by EO 13045 Section 1-101(a), EPA identified and assessed environmental 

health risks and safety risks that may disproportionately affect children in the revised risk 

assessment. Pursuant to U.S. EPA’s Guidance on Selecting Age Groups for Monitoring and 

Assessing Childhood Exposures to Environmental Contaminants, children are divided into seven 

distinct age cohorts: 1 to < 2 yr, 2 to < 3 yr, 3 to < 6 yr 6 to < 11 yr, 11 to < 16 yr, 16 to < 21 yr, 

and infants (< 1 yr). Using exposure factors for each of these cohorts, EPA calculated cancer and 

noncancer risk results in both the screening and probabilistic phases of the assessment. In 

general, risks to infants tended to be higher than other childhood cohorts, and also higher than 

risks to adults. However, for drinking water cancer risks, the longer exposures for adults led to 

the highest risks. Screening risks exceeded EPA’s human health criteria for children exposed to 

contaminated air, soil, and food resulting from fugitive dust emissions and runoff. Similarly, 90th

percentile child cancer and noncancer risks exceeded the human health criteria for the ground 
Document submitted to conclude E.O.12866 Review

599

water to drinking water pathway under the full probabilistic analysis (Table 5-17 in the Human 

and Ecological Risk Assessment of Coal Combustion Wastes). As ordered by EO13045 Section 

101(b) EPA has ensured that the standard addresses disproportionate risks to children that result 

from environmental health risks. The results of the screening assessment finds that risks fell 

below the criteria when wetting and run-on/runoff controls required by the rule are considered.

Under the full probabilistic analysis, composite liners required by the rule for new waste 

management units showed the ability to reduce the 90th percentile child cancer and noncancer 

risks for the ground water to drinking water pathway to well below EPA’s criteria. Additionally, 

the ground water monitoring and corrective action required by the rule will reduce risks from 

current waste management units. Thus, EPA believes that this rule will be protective of 

children’s health.

In general, because the pollution control requirements under the CCR rule will reduce 

health and environmental exposure risks at all coal-fired electric utility plants, the CCR rule is 

not expected to create additional or new risks to children.

H. Executive Order 13211: Actions Concerning Regulations That Significantly Affect 

Energy Supply, Distribution, or Use

[Note: This section will be revised once EPA completes its analysis of the impacts of this 

regulation using the “IPM model.”]

Executive Order 13211 (66 FR 28355 (May 22, 2001)) requires EPA to prepare and 

submit a Statement of Energy Effects to the Administrator of the Office of Information and 

Regulatory Affairs, Office of Management and Budget (OMB), for actions identified as 

“significant energy actions.” This action, which is a significant regulatory action under Executive 

Order 12866, is likely to have a significant adverse effect on the supply, distribution, or use of 
Document submitted to conclude E.O.12866 Review

600

energy based on the results of the electricity price impact estimates of the Regulatory Impact 

Analysis (RIA) for this action. We have prepared a Statement of Energy Effects for this action.

According to Executive Order 13211, the Statement should address (i) any adverse 

effects on energy supply, distribution, or use, (including a shortfall in supply, price increases, 

and increased use of foreign supplies) should the proposal be implemented, and (ii) reasonable 

alternatives to the action with adverse energy effects and the expected effects of such alternatives 

on energy supply, distribution, and use.

The potential impact of the final CCR rule on electricity prices is analyzed relative to the 

“in excess of one percent” threshold which is one of nine alternative numerical indicators 

established by OMB for defining “significant adverse effect” under Executive Order 13211.232 

The RIA estimates potential increases in wholesale electricity prices for 22 North American 

Electric Reliability Corporation (NERC) regions. In addition, the analysis focuses on potential 

changes in electricity prices in 2019. The analysis focuses on this relatively early year in the 

analytic time horizon examined in the RIA to minimize uncertainty in the estimated electricity 

price impacts. In addition, under the provisions of the rule, the year 2019 is one year after 

impoundments undergo closure or wet/dry conversion if they are found to be leaking. Therefore, 

2019 represents a high-cost year relative to other years in the analytic time horizon, and the 

analysis presented here will likely yield conservative estimates of the rule’s impact on electricity 

prices.

Using a nationwide relationship between changes in electricity production costs and 

changes in wholesale electricity prices obtained from nearly 30 IPM runs for the year 2015 from 

 

232 OMB defines nine alternative numerical indicators of “significant adverse effect” on energy supply, 

distribution, or use in Section 4 of its “Memorandum for Heads of Executive Departments and Agencies, 

and Independent Regulatory Agencies,” M-01-27, July 13, 2001.
Document submitted to conclude E.O.12866 Review

601

other EPA IPM analyses. The weighted average nationwide potential increase in the wholesale 

price of electricity is not expected to exceed one percent (i.e., 0.61%). However, for one of the 

22 NERC regions (the Western Electricity Coordinating Council / Northwest Power Pool Area 

consisting of the States Washington; Oregon; Idaho; Wyoming; Montana; Nevada; and, Utah and 

a small portion of Northern California), the RIA projects a potential price increase above one 

percent (i.e., 1.11%).

Finally, any retail electricity price increases, if they occur, would have the effect of 

offsetting a portion of the compliance costs to electric utilities estimated in the RIA, as the 

utilities would be recovering costs through price increases to customers. Therefore, these impacts 

are not additive to total rule costs, but would instead offset costs to utilities estimated in the RIA.

Only one region may slightly exceed a one percent electricity price increase, which the 

RIA estimated without considering the potential reduction in such impact with the compliance 

deadline flexibility of this action for CCR surface impoundments. Thus all regions are likely to 

experience less than one percent electricity price impacts of this action. Therefore, this Statement 

does not address reasonable alternatives to the action because EPA does not expect this action to 

have adverse energy effects as defined by OMB.

I. National Technology Transfer and Advancement Act

Section 12(d) of the National Technology Transfer and Advancement Act of 1995 

(“NTTAA”), Public Law No. 104-113, 12(d) (15 U.S.C. 272 note) directs EPA to use voluntary 

consensus standards in its regulatory activities unless to do so would be inconsistent with 

applicable law or otherwise impractical. Voluntary consensus standards are technical standards 

(e.g., materials specifications, test methods, sampling procedures, and business practices) that are 

developed or adopted by voluntary consensus standards bodies. NTTAA directs EPA to provide 
Document submitted to conclude E.O.12866 Review

602

Congress, through OMB, explanations when the Agency decides not to use available and 

applicable voluntary consensus standards. 

This rulemaking involves technical standards. EPA has decided to use the following 

technical standards in this rule: (1) RCRA Subpart D, Section 257.70 liner design criteria for 

new CCR landfills and any lateral expansion of a CCR landfill includes voluntary consensus 

standards developed by ASTM International and EPA test methods such as SW-846, (2) Section 

257.71 liner design criteria for existing CCR surface impoundments include voluntary consensus 

standards developed by ASTM International and EPA test methods such as SW-846, (3) Section 

257.72 liner design criteria for new CCR surface impoundments and any lateral expansion of a 

CCR surface impoundment include voluntary consensus standards developed by ASTM 

International and EPA test methods such as SW-846, and (4) Section 257.73 structural stability 

standards for new and existing surface impoundments use the ASTM D 698 and 1557 standards 

for embankment compaction.

J. Executive Order 12898: Federal Actions to Address Environmental Justice in Minority 

Populations and Low-Income Populations

Executive Order (EO) 12898 (59 FR 7629, Feb. 16, 1994) establishes federal executive 

policy on environmental justice. Its main provision directs federal agencies, to the greatest extent 

practicable and permitted by law, to make environmental justice part of their mission by 

identifying and addressing, as appropriate, disproportionately high and adverse human health or 

environmental effects of their programs, policies, and activities on minority populations and lowincome populations in the United States. 

EPA has determined that this final rule will not have disproportionately high and adverse 

human health or environmental effects on minority or low-income populations because it 
Document submitted to conclude E.O.12866 Review

603

increases the level of environmental protection for all affected populations without having any 

disproportionately high and adverse human health or environmental effects on any population, 

including any minority or low-income population.

EPA’s risk assessment for this action did not separately evaluate either minority or low 

income populations. However, to evaluate the demographic characteristics of communities that 

may be affected by the CCR rule, the RIA compares the demographic characteristics of 

populations surrounding coal-fired electric utility plants with broader population data for two 

geographic areas: (1) one-mile radius from CCR management units (i.e., landfills and 

impoundments) likely to be affected by groundwater releases from both landfills and 

impoundments; and (2) watershed catchment areas downstream of surface impoundments that 

receive surface water runoff and releases from CCR impoundments and are at risk of being 

contaminated from CCR impoundment discharges (e.g., unintentional overflows, structural 

failures, and intentional periodic discharges). 

For the population as a whole 24.8% belong to a minority group and 11.3% falls below 

the Federal Poverty Level. For the population living within one mile of plants with surface 

impoundments 16.1% belong to a minority group and 13.2 % live below the Federal Poverty 

Level. These minority and low-income populations are not disproportionately high compared to 

the general population. The percentage of minority residents of the entire population living 

within the catchment areas downstream of surface impoundments is disproportionately high 

relative to the general population, i.e., 28.7%, versus 24.8% for the national population. Also, 

the percentage of the population within the catchment areas of surface impoundments that is 

below the Federal Poverty Level is disproportionately high compared with the general 

population, i.e., 18.6% versus 11.3% nationally. 
Document submitted to conclude E.O.12866 Review

604

Comparing the population percentages of minority and low income residents within one 

mile of landfills to those percentages in the general population, EPA found that minority and 

low-income residents make up a smaller percentage of the populations near landfills than they do 

in the general population, i.e., minorities comprised 16.6% of the population near landfills versus 

24.8% nationwide and low-income residents comprised 8.6% of the population near landfills

versus 11.3% nationwide. In summary, although populations within the catchment areas of 

plants with surface impoundments appear to have disproportionately high percentages of 

minority and low-income residents relative to the nationwide average, populations surrounding 

plants with landfills do not. Because landfills are less likely than impoundments to experience 

surface water runoff and releases, catchment areas were not considered for landfills.

Because the CCR rule is risk-reducing, with reductions in risk occurring largely within 

the surface water catchment zones around, and groundwater beneath, coal-fired electric utility 

plants, the rule will not result in new disproportionate risks to minority or low-income 

populations.

K. Congressional Review Act

The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the Small Business 

Regulatory Enforcement Fairness Act of 1996, generally provides that before a rule may take 

effect, the agency promulgating the rule must submit a rule report, which includes a copy of the 

rule, to each House of the Congress and to the Comptroller General of the United States. EPA 

will submit a report containing this rule and other required information to the U.S. Senate, the 

U.S. House of Representatives, and the Comptroller General of the United States prior to 

publication of the rule in the Federal Register. A Major rule cannot take effect until 60 days after 
Document submitted to conclude E.O.12866 Review

605

it is published in the Federal Register. This action is a “major rule” as defined by 5 U.S.C. 

804(2). This rule will be effective 60 days after its publication in the Federal Register.

List of Subjects

40 CFR part 257

Environmental protection, Beneficial use, Coal combustion products, Coal combustion

residuals, Coal combustion waste, Disposal, Hazardous waste, Landfill, Surface impoundment.

40 CFR part 261

Environmental protection, Hazardous waste, Recycling, Reporting and recordkeeping

requirements.

Dated: 

Gina McCarthy,

Administrator.
Document submitted to conclude E.O.12866 Review

606

For the reasons set out in the preamble, title 40, chapter I, of the Code of Federal 

Regulations is amended as follows:

PART 257—CRITERIA FOR CLASSIFICATION OF SOLID WASTE DISPOSAL 

FACILITIES AND PRACTICES

1. The authority citation for part 257 continues to read as follows:

Authority: 42 U.S.C. 6907(a)(3), 6912(a)(1), 6944(a); 33 U.S.C. 1345(d) and (e).

2. Section 257.1 is amended by:

a. Adding a sentence at the end of paragraph (a) introductory text;

b. Revising paragraphs (a)(1) and (a)(2); and

c. Adding paragraph (c)(12).

The revisions and additions read as follows: 

§ 257.1 Scope and purpose.

(a) * * * Unless otherwise provided, the criteria in §§ 257.50 through 257.107 are 

adopted for determining which CCR landfills and CCR surface impoundments pose a reasonable 

probability of adverse effects on health or the environment under sections 1008(a)(3) and 

4004(a) of the Act.

(1) Facilities failing to satisfy any of the criteria in §§ 257.1 through 257.4 or §§ 

257.5 through 257.30 or §§ 257.50 through 257.107 are considered open dumps, which are 

prohibited under section 4005 of the Act.

(2) Practices failing to satisfy any of the criteria in §§ 257.1 through 257.4 or §§ 

257.5 through 257.30 or §§ 257.50 through 257.107 constitute open dumping, which is 

prohibited under section 4005 of the Act.
Document submitted to conclude E.O.12866 Review

607

* * * * *

(c) * * *

(12) Except as otherwise specifically provided in subpart D of this part, the criteria in 

subpart A of this part do not apply to CCR landfills, CCR surface impoundments, and lateral 

expansions of CCR units, as those terms are defined in subpart D of this part. Such units are 

instead subject to subpart D of this part.

3. Section 257.2 is amended by adding in alphabetical order definitions for “CCR 

landfill” and “CCR surface impoundment” to read as follows:

§ 257.2 Definitions.

* * * * *

CCR landfill means an area of land or an excavation that receives CCR and which is not a 

surface impoundment, an underground injection well, a salt dome formation, a salt bed 

formation, an underground or surface mine, or a cave. For purposes of this subpart, a CCR 

landfill also includes sand and gravel pits and quarries that receive CCR, CCR piles, and any 

practice that does not meet the definition of a beneficial use of CCR.

CCR surface impoundment means a natural topographic depression, man-made 

excavation, or diked area, which is designed to hold an accumulation of CCR and liquids, and 

the unit treats, stores, or disposes of CCR.

* * * * *

4. Part 257 is amended by:

a. Adding and reserving Subpart C; and

b. Adding Subpart D to read as follows:

Subpart C—[Reserved]
Document submitted to conclude E.O.12866 Review

608

Subpart D—Standards for the Disposal of Coal Combustion Residuals in Landfills 

and Surface Impoundments

General Provisions

Sec.

257.50 Scope and purpose.

257.51 Effective date of this subpart.

257.52 Applicability of other regulations.

257.53 Definitions.

Location Restrictions

257.60 Placement above the uppermost aquifer.

257.61 Wetlands.

257.62 Fault areas.

257.63 Seismic impact zones.

257.64 Unstable areas.

Design Criteria

257.70 Design criteria for new CCR landfills and any lateral expansion of a CCR 

landfill.

257.71 Liner design criteria for existing CCR surface impoundments.

257.72 Design criteria for new CCR surface impoundments and any lateral expansion of 

a CCR surface impoundment.

257.73 Structural integrity criteria for existing CCR surface impoundments.
Document submitted to conclude E.O.12866 Review

609

257.74 Structural integrity criteria for new CCR surface impoundments and any lateral 

expansion of a CCR surface impoundment.

Operating Criteria

257.80 Air criteria.

257.81 Run-on and run-off controls for CCR landfills.

257.82 Hydrologic and hydraulic capacity requirements for CCR surface impoundments.

257.83 Inspection requirements for CCR surface impoundments.

257.84 Inspection requirements for CCR landfills.

Groundwater Monitoring and Corrective Action

257.90 Applicability.

257.91 Groundwater monitoring systems.

257.92 [Reserved]

257.93 Groundwater sampling and analysis requirements.

257.94 Detection monitoring program.

257.95 Assessment monitoring program.

257.96 Assessment of corrective measures.

257.97 Selection of remedy.

257.98 Implementation of the corrective action program.

Closure and Post-Closure Care

257.100 Inactive CCR surface impoundments.

257.101 Closure of CCR landfills and CCR surface impoundments.

257.102 Criteria for conducting closure of CCR landfills and CCR surface 

impoundments.
Document submitted to conclude E.O.12866 Review

610

257.103 Alternative closure requirements.

257.104 Post-closure care requirements.

Recordkeeping, Notification, and Posting of Information to the Internet

257.105 Recordkeeping requirements.

257.106 Notification requirements.

257.107 Publicly accessible internet site requirements.

Subpart D—Standards for the Disposal of Coal Combustion Residuals in Landfills 

and Surface Impoundments

§ 257.50 Scope and purpose.

(a) This subpart establishes minimum national criteria for purposes of determining 

which solid waste disposal facilities and solid waste management practices do not pose a 

reasonable probability of adverse effects on health or the environment under sections 1008(a)(3) 

and 4004(a) of the Resource Conservation and Recovery Act. 

(b) This subpart applies to owners and operators of new and existing landfills and 

surface impoundments, including any lateral expansions of such units that dispose or otherwise 

engage in solid waste management of CCR generated from the combustion of coal at electric 

utilities and independent power producers. Unless otherwise provided in this subpart, these 

requirements also apply to disposal units located off-site of the electric utility or independent 

power producer. This subpart also applies to any practice that does not meet the definition of a 

beneficial use of CCR.

(c) This subpart also applies to inactive CCR surface impoundments at active electric 

utilities or independent power producers, regardless of the fuel currently used at the facility to 

produce electricity.
Document submitted to conclude E.O.12866 Review

611

(d) This subpart does not apply to CCR landfills that have ceased receiving CCR 

prior to [INSERT DATE 6 MONTHS AFTER DATE OF PUBLICATION IN THE 

FEDERAL REGISTER].

(e) This subpart does not apply to electric utilities or independent power producers 

that have ceased producing electricity prior to [INSERT DATE 6 MONTHS AFTER DATE 

OF PUBLICATION IN THE FEDERAL REGISTER].

(f) This subpart does not apply to wastes, including fly ash, bottom ash, boiler slag, 

and flue gas desulfurization materials generated at facilities that are not part of an electric utility 

or independent power producer, such as manufacturing facilities, universities, and hospitals. 

This subpart also does not apply to fly ash, bottom ash, boiler slag, and flue gas desulfurization 

materials, generated primarily from the combustion of fuels (including other fossil fuels) other 

than coal, for the purpose of generating electricity unless the fuel burned consists of more than 

fifty percent (50%) coal on a total heat input or mass input basis, whichever results in the greater 

mass feed rate of coal. 

(g) This subpart does not apply to practices that meet the definition of a beneficial use 

of CCR. 

(h) This subpart does not apply to CCR placement at active or abandoned 

underground or surface coal mines.

(i) This subpart does not apply to municipal solid waste landfills that receive CCR.

§ 257.51 Effective date of this subpart.

The requirements of this subpart take effect on [INSERT DATE 6 MONTHS AFTER 

DATE OF PUBLICATION IN THE FEDERAL REGISTER].

§ 257.52 Applicability of other regulations.
Document submitted to conclude E.O.12866 Review

612

(a) Compliance with the requirements of this subpart does not affect the need for the 

owner or operator of a CCR landfill, CCR surface impoundment, or lateral expansion of a CCR 

unit to comply with all other applicable federal, state, tribal, or local laws or other requirements.

(b) Any CCR landfill, CCR surface impoundment, or lateral expansion of a CCR unit 

continues to be subject to the requirements in §§ 257.3-1, 257.3-2, and 257.3-3.

§ 257.53 Definitions.

The following definitions apply to this subpart. Terms not defined in this section have 

the meaning given by RCRA.

Acre foot means the volume of one acre of surface area to a depth of one foot.

Active facility or active electric utilities or independent power producers means any 

facility subject to the requirements of this subpart that is in operation on [INSERT DATE 180 

DAYS AFTER THE DATE OF PUBLICATION IN THE FEDERAL REGISTER]. An 

electric utility or independent power producer is in operation if it is generating electricity that is 

provided to electric power transmission systems or to electric power distribution systems on or 

after [INSERT DATE 180 DAYS AFTER THE DATE OF PUBLICATION IN THE 

FEDERAL REGISTER]. An off-site disposal facility is in operation if it is accepting or 

managing CCR on or after [INSERT DATE 180 DAYS AFTER THE DATE OF 

PUBLICATION IN THE FEDERAL REGISTER].

Active life or in operation means the period of operation beginning with the initial 

placement of CCR in the CCR unit and ending at completion of closure activities in accordance 

with § 257.102.

Active portion means that part of the CCR unit that has received or is receiving CCR or 

non-CCR waste and that has not completed closure in accordance with § 257.102.
Document submitted to conclude E.O.12866 Review

613

Aquifer means a geologic formation, group of formations, or portion of a formation 

capable of yielding usable quantities of groundwater to wells or springs.

Area-capacity curves means graphic curves which readily show the reservoir water 

surface area, in acres, at different elevations from the bottom of the reservoir to the maximum 

water surface, and the capacity or volume, in acre-feet, of the water contained in the reservoir at 

various elevations.

Areas susceptible to mass movement means those areas of influence (i.e., areas 

characterized as having an active or substantial possibility of mass movement) where, because of 

natural or human-induced events, the movement of earthen material at, beneath, or adjacent to 

the CCR unit results in the downslope transport of soil and rock material by means of 

gravitational influence. Areas of mass movement include, but are not limited to, landslides, 

avalanches, debris slides and flows, soil fluctuation, block sliding, and rock fall.

Beneficial use of CCR means the CCR meet all of the following conditions:

(1) The CCR must provide a functional benefit;

(2) The CCR must substitute for the use of a virgin material, conserving natural resources 

that would otherwise need to be obtained through practices, such as extraction;

(3) The use of the CCR must meet relevant product specifications, regulatory standards or 

design standards when available, and when such standards are not available, the CCR is not used 

in excess quantities; and

(4) When unencapsulated use of CCR involving placement on the land of 12,400 tons or 

more in non-roadway applications, the user must demonstrate and keep records, and provide 

such documentation upon request, that environmental releases to groundwater, surface water, soil 

and air are comparable to or lower than those from analogous products made without CCR, or 
Document submitted to conclude E.O.12866 Review

614

that environmental releases to groundwater, surface water, soil and air will be at or below 

relevant regulatory and health-based benchmarks for human and ecological receptors during use.

Closed means placement of CCR in a CCR unit has ceased, and the owner or operator has 

completed closure of the CCR unit in accordance with § 257.102 and has initiated post-closure 

care in accordance with § 257.104.

Coal combustion residuals (CCR) means fly ash, bottom ash, boiler slag, and flue gas 

desulfurization materials generated from burning coal for the purpose of generating electricity by 

electric utilities and independent power producers. 

CCR fugitive dust means solid airborne particulate matter that contains or is derived from 

CCR, emitted from any source other than a stack or chimney.

CCR landfill or landfill means an area of land or an excavation that receives CCR and 

which is not a surface impoundment, an underground injection well, a salt dome formation, a salt 

bed formation, an underground or surface mine, or a cave. For purposes of this subpart, a CCR 

landfill also includes sand and gravel pits and quarries that receive CCR, CCR piles, and any 

practice that does not meet the definition of a beneficial use of CCR.

CCR pile or pile means any non-containerized accumulation of solid, non-flowing CCR 

that is placed on the land. CCR that is beneficially used off-site is not a CCR pile. 

CCR surface impoundment or impoundment means a natural topographic depression, 

man-made excavation, or diked area, which is designed to hold an accumulation of CCR and 

liquids, and the unit treats, stores, or disposes of CCR.

CCR unit means any CCR landfill, CCR surface impoundment, or lateral expansion of a 

CCR unit, or a combination of more than one of these units, based on the context of the 
Document submitted to conclude E.O.12866 Review

615

paragraph(s) in which it is used. This term includes both new and existing units, unless 

otherwise specified.

Dike means an embankment, berm, or ridge of either natural or man-made materials used 

to prevent the movement of liquids, sludges, solids, or other materials.

Displacement means the relative movement of any two sides of a fault measured in any 

direction.

Disposal means the discharge, deposit, injection, dumping, spilling, leaking, or placing of 

any solid waste as defined in section 1004(27) of the Resource Conservation and Recovery Act 

into or on any land or water so that such solid waste, or constituent thereof, may enter the 

environment or be emitted into the air or discharged into any waters, including groundwaters. 

For purposes of this subpart, disposal does not include the storage or the beneficial use of CCR. 

Downstream toe means the junction of the downstream slope or face of the CCR surface 

impoundment with the ground surface.

Encapsulated beneficial use means a beneficial use of CCR that binds the CCR into a 

solid matrix that minimizes its mobilization into the surrounding environment.

Existing CCR landfill means a CCR landfill that receives CCR both before and after 

[INSERT DATE 180 DAYS AFTER THE DATE OF PUBLICATION IN THE FEDERAL 

REGISTER], or for which construction commenced prior to [INSERT DATE 180 DAYS 

AFTER THE DATE OF PUBLICATION IN THE FEDERAL REGISTER] and receives 

CCR on or after [INSERT DATE 180 DAYS AFTER THE DATE OF PUBLICATION IN 

THE FEDERAL REGISTER]. A CCR landfill has commenced construction if the owner or 

operator has obtained the federal, state, and local approvals or permits necessary to begin 

physical construction and a continuous on-site, physical construction program had begun prior to 
Document submitted to conclude E.O.12866 Review

616

[INSERT DATE 180 DAYS AFTER THE DATE OF PUBLICATION IN THE FEDERAL 

REGISTER].

Existing CCR surface impoundment means a CCR surface impoundment that receives 

CCR both before and after [INSERT DATE 180 DAYS AFTER THE DATE OF 

PUBLICATION IN THE FEDERAL REGISTER], or for which construction commenced 

prior to [INSERT DATE 180 DAYS AFTER THE DATE OF PUBLICATION IN THE 

FEDERAL REGISTER] and receives CCR on or after [INSERT DATE 180 DAYS AFTER 

THE DATE OF PUBLICATION IN THE FEDERAL REGISTER]. A CCR surface 

impoundment has commenced construction if the owner or operator has obtained the federal, 

state, and local approvals or permits necessary to begin physical construction and a continuous 

on-site, physical construction program had begun prior to [INSERT DATE 180 DAYS AFTER 

THE DATE OF PUBLICATION IN THE FEDERAL REGISTER].

Facility means all contiguous land, and structures, other appurtenances, and 

improvements on the land, used for treating, storing, disposing, or otherwise conducting solid 

waste management of CCR. A facility may consist of several treatment, storage, or disposal 

operational units (e.g., one or more landfills, surface impoundments, or combinations of them).

Factor of safety (Safety factor) means the ratio of the forces tending to resist the failure of 

a structure to the forces tending to cause such failure as determined by accepted engineering 

practice.

Fault means a fracture or a zone of fractures in any material along which strata on one 

side have been displaced with respect to that on the other side.

Flood hydrograph means a graph showing, for a given point on a stream, the discharge, 

height, or other characteristic of a flood as a function of time.
Document submitted to conclude E.O.12866 Review

617

Freeboard means the vertical distance between the lowest point on the crest of the 

impoundment dike and the surface of the waste contained therein.

Free liquids means liquids that readily separate from the solid portion of a waste under 

ambient temperature and pressure.

Groundwater means water below the land surface in a zone of saturation.

Hazard potential classification means the possible adverse incremental consequences that 

result from the release of water or stored contents due to failure of the diked CCR surface 

impoundment or mis-operation of the diked CCR surface impoundment or its 

appurtenances. The hazardous potential classifications include high hazard potential CCR 

surface impoundment, significant hazard potential CCR surface impoundment, and low hazard 

potential CCR surface impoundment, which terms mean:

(1) High hazard potential CCR surface impoundment means a diked surface 

impoundment where failure or mis-operation will probably cause loss of human life.

(2) Low hazard potential CCR surface impoundment means a diked surface 

impoundment where failure or mis-operation results in no probable loss of human life and low 

economic and/or environmental losses. Losses are principally limited to the surface 

impoundment owner’s property.

(3) Significant hazard potential CCR surface impoundment means a diked surface 

impoundment where failure or mis-operation results in no probable loss of human life, but can 

cause economic loss, environmental damage, disruption of lifeline facilities, or impact other 

concerns.
Document submitted to conclude E.O.12866 Review

618

Height means the vertical measurement from the downstream toe of the CCR surface 

impoundment at its lowest point to the lowest elevation of the crest of the CCR surface 

impoundment.

Holocene means the most recent epoch of the Quaternary period, extending from the end 

of the Pleistocene Epoch, at 11,700 years before present, to present.

Hydraulic conductivity means the rate at which water can move through a permeable 

medium (i.e., the coefficient of permeability).

Inactive CCR surface impoundment means a CCR surface impoundment that no longer

receives CCR on or after [INSERT DATE 180 DAYS FROM THE DATE OF 

PUBLICATION IN THE FEDERAL REGISTER] and still contains both CCR and liquids on 

or after [INSERT DATE 180 DAYS FROM THE DATE OF PUBLICATION IN THE 

FEDERAL REGISTER].

Incised CCR surface impoundment means a CCR surface impoundment which is 

constructed by excavating entirely below the natural ground surface, holds an accumulation of 

CCR entirely below the adjacent natural ground surface, and does not consist of any constructed 

diked portion.

Indian country or Indian lands means: 

(1) All land within the limits of any Indian reservation under the jurisdiction of the 

United States Government, notwithstanding the issuance of any patent, and including rights-ofway running throughout the reservation;

(2) All dependent Indian communities within the borders of the United States whether 

within the original or subsequently acquired territory thereof, and whether within or without the 

limits of the State; and 
Document submitted to conclude E.O.12866 Review

619

(3) All Indian allotments, the Indian titles to which have not been extinguished, including 

rights of way running through the same. 

Indian Tribe or Tribe means any Indian tribe, band, nation, or community recognized by 

the Secretary of the Interior and exercising substantial governmental duties and powers on Indian 

lands. 

Inflow design flood means the flood hydrograph that is used in the design or modification 

of the CCR surface impoundments and its appurtenant works.

In operation means the same as active life.

Karst terrain means an area where karst topography, with its characteristic erosional 

surface and subterranean features, is developed as the result of dissolution of limestone, 

dolomite, or other soluble rock. Characteristic physiographic features present in karst terranes 

include, but are not limited to, dolines, collapse shafts (sinkholes), sinking streams, caves, seeps, 

large springs, and blind valleys.

Lateral expansion means a horizontal expansion of the waste boundaries of an existing 

CCR landfill or existing CCR surface impoundment made after [INSERT DATE 180 DAYS 

FROM THE DATE OF PUBLICATION IN THE FEDERAL REGISTER].

Liquefaction factor of safety means the factor of safety (safety factor) determined using 

analysis under liquefaction conditions.

Lithified earth material means all rock, including all naturally occurring and naturally 

formed aggregates or masses of minerals or small particles of older rock that formed by 

crystallization of magma or by induration of loose sediments. This term does not include manmade materials, such as fill, concrete, and asphalt, or unconsolidated earth materials, soil, or 

regolith lying at or near the earth surface.
Document submitted to conclude E.O.12866 Review

620

Maximum horizontal acceleration in lithified earth material means the maximum 

expected horizontal acceleration at the ground surface as depicted on a seismic hazard map, with 

a 98% or greater probability that the acceleration will not be exceeded in 50 years, or the 

maximum expected horizontal acceleration based on a site-specific seismic risk assessment.

New CCR landfill means a CCR landfill or lateral expansion of a CCR landfill that first 

receives CCR or commences construction after [INSERT DATE 180 DAYS FROM THE 

DATE OF PUBLICATION IN THE FEDERAL REGISTER]. A new CCR landfill has 

commenced construction if the owner or operator has obtained the federal, state, and local 

approvals or permits necessary to begin physical construction and a continuous on-site, physical 

construction program had begun after [INSERT DATE 180 DAYS AFTER THE DATE OF 

PUBLICATION IN THE FEDERAL REGISTER]. Overfills are also considered new CCR 

landfills.

New CCR surface impoundment means a CCR surface impoundment or lateral expansion 

of an existing or new CCR surface impoundment that first receives CCR or commences 

construction after [INSERT DATE 180 DAYS FROM THE DATE OF PUBLICATION IN 

THE FEDERAL REGISTER]. A new CCR surface impoundment has commenced 

construction if the owner or operator has obtained the federal, state, and local approvals or 

permits necessary to begin physical construction and a continuous on-site, physical construction 

program had begun after [INSERT DATE 180 DAYS AFTER THE DATE OF 

PUBLICATION IN THE FEDERAL REGISTER].

Operator means the person(s) responsible for the overall operation of a CCR unit.

Overfill means a new CCR landfill constructed over a closed CCR surface impoundment.

Owner means the person(s) who owns a CCR unit or part of a CCR unit.
Document submitted to conclude E.O.12866 Review

621

Poor foundation conditions mean those areas where features exist which indicate that a 

natural or human-induced event may result in inadequate foundation support for the structural 

components of an existing or new CCR unit. For example, failure to maintain static and seismic 

factors of safety as required in §§ 257.73(e) and 257.74(e) would cause a poor foundation 

condition.

Probable maximum flood means the flood that may be expected from the most severe 

combination of critical meteorologic and hydrologic conditions that are reasonably possible in 

the drainage basin.

Qualified person means a person or persons trained to recognize specific appearances of 

structural weakness and other conditions which are disrupting or have the potential to disrupt the 

operation or safety of the CCR unit by visual observation and, if applicable, to monitor 

instrumentation.

Qualified professional engineer means an individual who is licensed by a state as a 

Professional Engineer to practice one or more disciplines of engineering and who is qualified by 

education, technical knowledge and experience to make the specific technical certifications 

required under this subpart. Professional engineers making these certifications must be currently 

licensed in the state where the CCR unit(s) is located.

Recognized and generally accepted good engineering practices means engineering 

maintenance or operation activities based on established codes, widely accepted standards, 

published technical reports, or a practice widely recommended throughout the industry. Such 

practices generally detail approved ways to perform specific engineering, inspection, or 

mechanical integrity activities. 
Document submitted to conclude E.O.12866 Review

622

Representative sample means a sample of a universe or whole (e.g., waste pile, lagoon, 

and groundwater) which can be expected to exhibit the average properties of the universe or 

whole. See EPA publication SW-846, Test Methods for Evaluating Solid Waste, 

Physical/Chemical Methods, Chapter 9 for a discussion and examples of representative samples.

Run-off means any rainwater, leachate, or other liquid that drains over land from any part 

of a CCR landfill or lateral expansion of a CCR landfill.

Run-on means any rainwater, leachate, or other liquid that drains over land onto any part 

of a CCR landfill or lateral expansion of a CCR landfill.

Sand and gravel pit or quarry means an excavation for the extraction of aggregate, 

minerals or metals. The term sand and gravel pit and/or quarry does not include subsurface or 

surface coal mines.

Seismic factor of safety means the factor of safety (safety factor) determined using 

analysis under earthquake conditions using the peak ground acceleration for a seismic event with 

a 2% probability of exceedance in 50 years, equivalent to a return period of approximately 2,500 

years, based on the U.S. Geological Survey (USGS) seismic hazard maps for seismic events with 

this return period for the region where the CCR surface impoundment is located.

Seismic impact zone means an area having a 2% or greater probability that the maximum 

expected horizontal acceleration, expressed as a percentage of the earth’s gravitational pull (g), 

will exceed 0.10 g in 50 years.

Slope protection means engineered or non-engineered measures installed on the upstream 

or downstream slope of the CCR surface impoundment to protect the slope against wave action 

or erosion, including but not limited to rock riprap, wooden pile, or concrete revetments, 

vegetated wave berms, concrete facing, gabions, geotextiles, or fascines.
Document submitted to conclude E.O.12866 Review

623

Solid waste management or management means the systematic administration of the 

activities which provide for the collection, source separation, storage, transportation, processing, 

treatment, or disposal of solid waste.

State means any of the fifty States in addition to the District of Columbia, the 

Commonwealth of Puerto Rico, the Virgin Islands, Guam, American Samoa, and the 

Commonwealth of the Northern Mariana Islands.

State Director means the chief administrative officer of the lead state agency responsible 

for implementing the state program regulating disposal in CCR landfills, CCR surface 

impoundments, and all lateral expansions of a CCR unit.

Static factor of safety means the factor of safety (safety factor) determined using analysis 

under the long-term, maximum storage pool loading condition, the maximum surcharge pool 

loading condition, and under the end-of-construction loading condition.

Structural components mean liners, leachate collection and removal systems, final covers, 

run-on and run-off systems, inflow design flood control systems, and any other component used 

in the construction and operation of the CCR unit that is necessary to ensure the integrity of the 

unit and that the contents of the unit are not released into the environment.

Unstable area means a location that is susceptible to natural or human-induced events or 

forces capable of impairing the integrity, including structural components of some or all of the 

CCR unit that are responsible for preventing releases from such unit. Unstable areas can 

include poor foundation conditions, areas susceptible to mass movements, and karst terrains.

Uppermost aquifer means the geologic formation nearest the natural ground surface that 

is an aquifer, as well as lower aquifers that are hydraulically interconnected with this aquifer 
Document submitted to conclude E.O.12866 Review

624

within the facility’s property boundary. Upper limit is measured at a point nearest to the natural 

ground surface to which the aquifer rises during the wet season.

Waste boundary means a vertical surface located at the hydraulically downgradient limit 

of the CCR unit. The vertical surface extends down into the uppermost aquifer.

Location Restrictions

§ 257.60 Placement above the uppermost aquifer.

(a) New CCR landfills, existing and new CCR surface impoundments, and all lateral 

expansions of CCR units must be constructed with a base that is located no less than 1.52 meters 

(five feet) above the upper limit of the uppermost aquifer, or must demonstrate that there will not 

be an intermittent, recurring, or sustained hydraulic connection between any portion of the base 

of the CCR unit and the uppermost aquifer due to normal fluctuations in groundwater elevations 

(including the seasonal high water table). The owner or operator must demonstrate by the dates 

specified in paragraph (c) of this section that the CCR unit meets the minimum requirements for 

placement above the uppermost aquifer.

(b) The owner or operator of the CCR unit must obtain a certification from a qualified 

professional engineer stating that the demonstration meets the requirements of paragraph (a) of 

this section.

(c) The owner or operator of the CCR unit must complete the demonstration required 

by paragraph (a) of this section by the date specified in either paragraph (c)(1) or (c)(2) of this 

section.

(1) For an existing CCR surface impoundment, the owner or operator must complete 

the demonstration no later than [INSERT DATE 42 MONTHS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER].
Document submitted to conclude E.O.12866 Review

625

(2) For a new CCR landfill, new CCR surface impoundment, or any lateral expansion

of a CCR unit, the owner or operator must complete the demonstration no later than the date of 

initial receipt of CCR in the CCR unit.

(3) The owner or operator has completed the demonstration required by paragraph (a) 

of this section when the demonstration is placed in the facility’s operating record as required by 

§ 257.105(e).

(4) An owner or operator of an existing CCR surface impoundment who fails to 

demonstrate compliance with the requirements of paragraph (a) of this section by the date 

specified in paragraph (c)(1) of this section is subject to the requirements of § 257.101(b)(1).

(5) An owner or operator of a new CCR landfill, new CCR surface impoundment, or 

any lateral expansion of a CCR unit who fails to make the demonstration showing compliance 

with the requirements of paragraph (a) of this section is prohibited from placing CCR in the CCR 

unit.

(d) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(e), the notification requirements specified in § 257.106(e), 

and the internet requirements specified in § 257.107(e).

§ 257.61 Wetlands.

(a) New CCR landfills, existing and new CCR surface impoundments, and all 

lateral expansions of CCR units must not be located in wetlands, as defined in § 232.2 of this 

chapter, unless the owner or operator demonstrates by the dates specified in paragraph (c) of this 

section that the CCR unit meets the requirements of paragraphs (a)(1) through (a)(5) of this 

section.
Document submitted to conclude E.O.12866 Review

626

(1) Where applicable under section 404 of the Clean Water Act or applicable state 

wetlands laws, a clear and objective rebuttal of the presumption that an alternative to the CCR 

unit is reasonably available that does not involve wetlands.

(2) The construction and operation of the CCR unit will not cause or contribute to any 

of the following:

(i) A violation of any applicable state or federal water quality standard;

(ii) A violation of any applicable toxic effluent standard or prohibition under section 

307 of the Clean Water Act;

(iii) Jeopardize the continued existence of endangered or threatened species or result 

in the destruction or adverse modification of a critical habitat, protected under the Endangered 

Species Act of 1973; and

(iv) A violation of any requirement under the Marine Protection, Research, and 

Sanctuaries Act of 1972 for the protection of a marine sanctuary.

(3) The CCR unit will not cause or contribute to significant degradation of wetlands 

by addressing all of the following factors:

(i) Erosion, stability, and migration potential of native wetland soils, muds and 

deposits used to support the CCR unit;

(ii) Erosion, stability, and migration potential of dredged and fill materials used to 

support the CCR unit;

(iii) The volume and chemical nature of the CCR;

(iv) Impacts on fish, wildlife, and other aquatic resources and their habitat from 

release of CCR;
Document submitted to conclude E.O.12866 Review

627

(v) The potential effects of catastrophic release of CCR to the wetland and the 

resulting impacts on the environment; and

(vi) Any additional factors, as necessary, to demonstrate that ecological resources in 

the wetland are sufficiently protected.

(4) To the extent required under section 404 of the Clean Water Act or applicable 

state wetlands laws, steps have been taken to attempt to achieve no net loss of wetlands (as 

defined by acreage and function) by first avoiding impacts to wetlands to the maximum extent 

reasonable as required by paragraph (a)(1) of this section, then minimizing unavoidable impacts 

to the maximum extent reasonable, and finally offsetting remaining unavoidable wetland impacts 

through all appropriate and reasonable compensatory mitigation actions (e.g., restoration of 

existing degraded wetlands or creation of man-made wetlands); and

(5) Sufficient information is available to make a reasoned determination with respect 

to the demonstrations in paragraphs (a)(1) through (a)(4) of this section.

(b) The owner or operator of the CCR unit must obtain a certification from a qualified 

professional engineer stating that the demonstration meets the requirements of paragraph (a) of 

this section.

(c) The owner or operator of the CCR unit must complete the demonstrations 

required by paragraph (a) of this section by the date specified in either paragraph (c)(1) or (c)(2) 

of this section.

(1) For an existing CCR surface impoundment, the owner or operator must complete 

the demonstration no later than [INSERT DATE 42 MONTHS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER].
Document submitted to conclude E.O.12866 Review

628

(2) For a new CCR landfill, new CCR surface impoundment, or any lateral expansion 

of a CCR unit, the owner or operator must complete the demonstration no later than the date of 

initial receipt of CCR in the CCR unit.

(3) The owner or operator has completed the demonstration required by paragraph (a) 

of this section when the demonstration is placed in the facility’s operating record as required by 

§ 257.105(e).

(4) An owner or operator of an existing CCR surface impoundment who fails to 

demonstrate compliance with the requirements of paragraph (a) of this section by the date 

specified in paragraph (c)(1) of this section is subject to the requirements of § 257.101(b)(1).

(5) An owner or operator of a new CCR landfill, new CCR surface impoundment, or 

any lateral expansion of a CCR unit who fails to make the demonstrations showing compliance 

with the requirements of paragraph (a) of this section is prohibited from placing CCR in the CCR 

unit.

(d) The owner or operator must comply with the recordkeeping requirements 

specified in § 257.105(e), the notification requirements specified in § 257.106(e), and the 

internet requirements specified in § 257.107(e).

§ 257.62 Fault areas.

(a) New CCR landfills, existing and new CCR surface impoundments, and all lateral 

expansions of CCR units must not be located within 60 meters (200 feet) of the outermost 

damage zone of a fault that has had displacement in Holocene time unless the owner or operator 

demonstrates by the dates specified in paragraph (c) of this section that an alternative setback 

distance of less than 60 meters (200 feet) will prevent damage to the structural integrity of the 

CCR unit.
Document submitted to conclude E.O.12866 Review

629

(b) The owner or operator of the CCR unit must obtain a certification from a qualified 

professional engineer stating that the demonstration meets the requirements of paragraph (a) of 

this section.

(c) The owner or operator of the CCR unit must complete the demonstration required 

by paragraph (a) of this section by the date specified in either paragraph (c)(1) or (c)(2) of this 

section.

(1) For an existing CCR surface impoundment, the owner or operator must complete 

the demonstration no later than [INSERT DATE 42 MONTHS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER].

(2) For a new CCR landfill, new CCR surface impoundment, or any lateral expansion 

of a CCR unit, the owner or operator must complete the demonstration no later than the date of 

initial receipt of CCR in the CCR unit.

(3) The owner or operator has completed the demonstration required by paragraph (a) 

of this section when the demonstration is placed in the facility’s operating record as required by 

§ 257.105(e).

(4) An owner or operator of an existing CCR surface impoundment who fails to 

demonstrate compliance with the requirements of paragraph (a) of this section by the date 

specified in paragraph (c)(1) of this section is subject to the requirements of § 257.101(b)(1).

(5) An owner or operator of a new CCR landfill, new CCR surface impoundment, or 

any lateral expansion of a CCR unit who fails to make the demonstration showing compliance 

with the requirements of paragraph (a) of this section is prohibited from placing CCR in the CCR 

unit.
Document submitted to conclude E.O.12866 Review

630

(d) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(e), the notification requirements specified in § 257.106(e), 

and the internet requirements specified in § 257.107(e).

§ 257.63 Seismic impact zones.

(a) New CCR landfills, existing and new CCR surface impoundments, and all lateral 

expansions of CCR units must not be located in seismic impact zones unless the owner or 

operator demonstrates by the dates specified in paragraph (c) of this section that all structural 

components including liners, leachate collection and removal systems, and surface water control 

systems, are designed to resist the maximum horizontal acceleration in lithified earth material for 

the site.

(b) The owner or operator of the CCR unit must obtain a certification from a qualified 

professional engineer stating that the demonstration meets the requirements of paragraph (a) of 

this section.

(c) The owner or operator of the CCR unit must complete the demonstration required 

by paragraph (a) of this section by the date specified in either paragraph (c)(1) or (c)(2) of this 

section.

(1) For an existing CCR surface impoundment, the owner or operator must complete 

the demonstration no later than [INSERT DATE 42 MONTHS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER].

(2) For a new CCR landfill, new CCR surface impoundment, or any lateral expansion 

of a CCR unit, the owner or operator must complete the demonstration no later than the date of 

initial receipt of CCR in the CCR unit.
Document submitted to conclude E.O.12866 Review

631

(3) The owner or operator has completed the demonstration required by paragraph (a) 

of this section when the demonstration is placed in the facility’s operating record as required by 

§ 257.105(e).

(4) An owner or operator of an existing CCR surface impoundment who fails to 

demonstrate compliance with the requirements of paragraph (a) of this section by the date 

specified in paragraph (c)(1) of this section is subject to the requirements of § 257.101(b)(1).

(5) An owner or operator of a new CCR landfill, new CCR surface impoundment, or 

any lateral expansion of a CCR unit who fails to make the demonstration showing compliance 

with the requirements of paragraph (a) of this section is prohibited from placing CCR in the CCR 

unit.

(d) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(e), the notification requirements specified in § 257.106(e), 

and the internet requirements specified in § 257.107(e).

§ 257.64 Unstable areas.

(a) An existing or new CCR landfill, existing or new CCR surface impoundment, or 

any lateral expansion of a CCR unit must not be located in an unstable area unless the owner or 

operator demonstrates by the dates specified in paragraph (d) of this section that recognized and 

generally accepted good engineering practices have been incorporated into the design of the 

CCR unit to ensure that the integrity of the structural components of the CCR unit will not be 

disrupted.

(b) The owner or operator must consider all of the following factors, at a minimum, 

when determining whether an area is unstable:

(1) On-site or local soil conditions that may result in significant differential settling;
Document submitted to conclude E.O.12866 Review

632

(2) On-site or local geologic or geomorphologic features; and

(3) On-site or local human-made features or events (both surface and subsurface).

(c) The owner or operator of the CCR unit must obtain a certification from a qualified 

professional engineer stating that the demonstration meets the requirements of paragraph (a) of 

this section.

(d) The owner or operator of the CCR unit must complete the demonstration required 

by paragraph (a) of this section by the date specified in either paragraph (d)(1) or (d)(2) of this 

section.

(1) For an existing CCR landfill or existing CCR surface impoundment, the owner or 

operator must complete the demonstration no later than [INSERT DATE 42 MONTHS 

AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER].

(2) For a new CCR landfill, new CCR surface impoundment, or any lateral expansion 

of a CCR unit, the owner or operator must complete the demonstration no later than the date of 

initial receipt of CCR in the CCR unit.

(3) The owner or operator has completed the demonstration required by paragraph (a) 

of this section when the demonstration is placed in the facility’s operating record as required by 

§ 257.105(e).

(4) An owner or operator of an existing CCR surface impoundment or existing CCR 

landfill who fails to demonstrate compliance with the requirements of paragraph (a) of this 

section by the date specified in paragraph (d)(1) of this section is subject to the requirements of § 

257.101(b)(1) or (d)(1), respectively.

(5) An owner or operator of a new CCR landfill, new CCR surface impoundment, or 

any lateral expansion of a CCR unit who fails to make the demonstration showing compliance 
Document submitted to conclude E.O.12866 Review

633

with the requirements of paragraph (a) of this section is prohibited from placing CCR in the CCR 

unit.

(e) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(e), the notification requirements specified in § 257.106(e), 

and the internet requirements specified in § 257.107(e).

Design Criteria

§ 257.70 Design criteria for new CCR landfills and any lateral expansion of a CCR 

landfill.

(a)(1) New CCR landfills and any lateral expansion of a CCR landfill must be designed, 

constructed, operated, and maintained with either a composite liner that meets the requirements 

of paragraph (b) of this section or an alternative composite liner that meets the requirements in 

paragraph (c) of this section, and a leachate collection and removal system that meets the 

requirements of paragraph (d) of this section.

(2) Prior to construction of an overfill the underlying surface impoundment must 

meet the requirements of §257.102(d).

(b) A composite liner must consist of two components; the upper component 

consisting of, at a minimum, a 30-mil geomembrane liner (GM), and the lower component 

consisting of at least a two-foot layer of compacted soil with a hydraulic conductivity of no more 

than 1x10-7centimeters per second (cm/sec). GM components consisting of high density 

polyethylene (HDPE) must be at least 60-mil thick. The GM or upper liner component must be 

installed in direct and uniform contact with the compacted soil or lower liner component. The 

composite liner must be:
Document submitted to conclude E.O.12866 Review

634

(1) Constructed of materials that have appropriate chemical properties and sufficient 

strength and thickness to prevent failure due to pressure gradients (including static head and 

external hydrogeologic forces), physical contact with the CCR or leachate to which they are 

exposed, climatic conditions, the stress of installation, and the stress of daily operation;

(2) Constructed of materials that provide appropriate shear resistance of the upper 

and lower component interface to prevent sliding of the upper component including on slopes;

(3) Placed upon a foundation or base capable of providing support to the liner and 

resistance to pressure gradients above and below the liner to prevent failure of the liner due to 

settlement, compression, or uplift; and

(4) Installed to cover all surrounding earth likely to be in contact with the CCR or 

leachate.

(c) If the owner or operator elects to install an alternative composite liner, all of the 

following requirements must be met: 

(1) An alternative composite liner must consist of two components; the upper 

component consisting of, at a minimum, a 30-mil GM, and a lower component, that is not a 

geomembrane, with a liquid flow rate no greater than the liquid flow rate of two feet of 

compacted soil with a hydraulic conductivity of no more than 1x10-7cm/sec. GM components 

consisting of high density polyethylene (HDPE) must be at least 60-mil thick. If the lower 

component of the alternative liner is compacted soil, the GM must be installed in direct and 

uniform contact with the compacted soil.

(2) The owner or operator must obtain certification from a qualified professional 

engineer that the liquid flow rate through the lower component of the alternative composite liner 

is no greater than the liquid flow rate through two feet of compacted soil with a hydraulic 
Document submitted to conclude E.O.12866 Review

635

conductivity of 1x10-7cm/sec. The hydraulic conductivity for the two feet of compacted soil 

used in the comparison shall be no greater than 1x10-7cm/sec. The hydraulic conductivity of 

any alternative to the two feet of compacted soil must be determined using recognized and 

generally accepted methods. The liquid flow rate comparison must be made using Equation 1 of 

this section, which is derived from Darcy’s Law for gravity flow through porous media.

(Eq. 1):

Q

A

= q = k (

h

t

+ 1)

Where,

Q = flow rate (cubic centimeters/second);

A = surface area of the liner (squared centimeters);

q = flow rate per unit area (cubic centimeters/second/squared centimeter);

k = hydraulic conductivity of the liner (centimeters/second);

h = hydraulic head above the liner (centimeters); and

t = thickness of the liner (centimeters).

(3) The alternative composite liner must meet the requirements specified in 

paragraphs (b)(1) through (b)(4) of this section.

(d) The leachate collection and removal system must be designed, constructed, 

operated, and maintained to collect and remove leachate from the landfill during the active life 

and post-closure care period. The leachate collection and removal system must be:

(1) Designed and operated to maintain less than a 30-centimeter depth of leachate 

over the composite liner or alternative composite liner;
Document submitted to conclude E.O.12866 Review

636

(2) Constructed of materials that are chemically resistant to the CCR and any nonCCR waste managed in the CCR unit and the leachate expected to be generated, and of sufficient 

strength and thickness to prevent collapse under the pressures exerted by overlying waste, waste 

cover materials, and equipment used at the CCR unit; and

(3) Designed and operated to minimize clogging during the active life and postclosure care period.

(e) Prior to construction of the CCR landfill or any lateral expansion of a CCR 

landfill, the owner or operator must obtain a certification from a qualified professional engineer 

that the design of the composite liner (or, if applicable, alternative composite liner) and the 

leachate collection and removal system meets the requirements of this section.

(f) Upon completion of construction of the CCR landfill or any lateral expansion of a 

CCR landfill, the owner or operator must obtain a certification from a qualified professional 

engineer that the composite liner (or, if applicable, alternative composite liner) and the leachate 

collection and removal system has been constructed in accordance with the requirements of this 

section.

(g) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(f), the notification requirements specified in § 257.106(f), 

and the internet requirements specified in § 257.107(f).

§ 257.71 Liner design criteria for existing CCR surface impoundments.

(a)(1) No later than [INSERT DATE 18 MONTHS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER], the owner or operator of an existing CCR 

surface impoundment must document whether or not such unit was constructed with any one of 

the following:
Document submitted to conclude E.O.12866 Review

637

(i) A liner consisting of a minimum of two feet of compacted soil with a hydraulic 

conductivity of no more than 1x10-7cm/sec; 

(ii) A composite liner that meets the requirements of § 257.70(b); or 

(iii) An alternative composite liner that meets the requirements of § 257.70(c).

(2) The hydraulic conductivity of the compacted soil must be determined using 

recognized and generally accepted methods.

(3) An existing CCR surface impoundment is considered to be an existing unlined 

CCR surface impoundment if either:

(i) The owner or operator of the CCR unit determines that the CCR unit is not 

constructed with a liner that meets the requirements of paragraphs (a)(1)(i), (a)(1)(ii), or 

(a)(1)(iii) of this section; or

(ii) The owner or operator of the CCR unit fails to document whether the CCR unit 

was constructed with a liner that meets the requirements of paragraphs (a)(1)(i), (a)(1)(ii), or 

(a)(1)(iii) of this section.

(4) All existing unlined CCR surface impoundments are subject to the requirements 

of § 257.101(a).

(b) The owner or operator of the CCR unit must obtain a certification from a 

qualified professional engineer attesting that the documentation as to whether a CCR unit meets 

the requirements of paragraph (a) of this section is accurate.

(c) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(f), the notification requirements specified in § 257.106(f), 

and the internet requirements specified in § 257.107(f).
Document submitted to conclude E.O.12866 Review

638

§ 257.72 Liner design criteria for new CCR surface impoundments and any lateral 

expansion of a CCR surface impoundment.

(a) New CCR surface impoundments and lateral expansions of existing and new CCR 

surface impoundments must be designed, constructed, operated, and maintained with either a 

composite liner or an alternative composite liner that meets the requirements of § 257.70(b) or 

(c).

(b) Any liner specified in this section must be installed to cover all surrounding earth 

likely to be in contact with CCR. Dikes shall not be constructed on top of the composite liner.

(c) Prior to construction of the CCR surface impoundment or any lateral expansion of 

a CCR surface impoundment, the owner or operator must obtain certification from a qualified 

professional engineer that the design of the composite liner or, if applicable, the design of an 

alternative composite liner complies with the requirements of this section.

(d) Upon completion, the owner or operator must obtain certification from a qualified 

professional engineer that the composite liner or if applicable, the alternative composite liner has 

been constructed in accordance with the requirements of this section.

(e) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(f), the notification requirements specified in § 257.106(f), 

and the internet requirements specified in § 257.107(f).

§ 257.73 Structural integrity criteria for existing CCR surface impoundments.

(a) The requirements of paragraphs (a)(1) through (a)(4) of this section apply to all 

existing CCR surface impoundments, except for those existing CCR surface impoundments that 

are incised CCR units. If an incised CCR surface impoundment is subsequently modified (e.g., a 

dike is constructed) such that the CCR unit no longer meets the definition of an incised CCR 
Document submitted to conclude E.O.12866 Review

639

unit, the CCR unit is subject to the requirements of paragraphs (a)(1) through (a)(4) of this 

section.

(1) No later than, [INSERT DATE 8 MONTHS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER], the owner or operator of the CCR unit 

must place on or immediately adjacent to the CCR unit a permanent identification marker, at 

least six feet high showing the identification number of the CCR unit, if one has been assigned 

by the state, the name associated with the CCR unit and the name of the owner or operator of the 

CCR unit.

(2) Periodic hazard potential classification assessments. (i) The owner or operator of 

the CCR unit must conduct initial and periodic hazard potential classification assessments of the 

CCR unit according to the timeframes specified in paragraph (f) of this section. The owner or 

operator must document the hazard potential classification of each CCR unit as either a high 

hazard potential CCR surface impoundment, a significant hazard potential CCR surface 

impoundment, or a low hazard potential CCR surface impoundment. The owner or operator 

must also document the basis for each hazard potential classification.

(ii) The owner or operator of the CCR unit must obtain a certification from a qualified 

professional engineer stating that the initial hazard potential classification and each subsequent 

periodic classification specified in paragraph (a)(2)(i) of this section was conducted in 

accordance with the requirements of this section.

(3) Emergency Action Plan (EAP). (i) Development of the plan. No later than 

[INSERT DATE 24 MONTHS AFTER DATE OF PUBLICATION IN THE FEDERAL 

REGISTER], the owner or operator of a CCR unit determined to be either a high hazard 

potential CCR surface impoundment or a significant hazard potential CCR surface impoundment 
Document submitted to conclude E.O.12866 Review

640

under paragraph (a)(2) of this section must prepare and maintain a written EAP. At a minimum, 

the EAP must:

(A) Define the events or circumstances involving the CCR unit that represent a safety 

emergency, along with a description of the procedures that will be followed to detect a safety 

emergency in a timely manner;

(B) Define responsible persons, their respective responsibilities, and notification 

procedures in the event of a safety emergency involving the CCR unit;

(C) Provide contact information of emergency responders;

(D) Include a map which delineates the downstream area which would be affected in 

the event of a CCR unit failure and a physical description of the CCR unit; and

(E) Include provisions for an annual face-to-face meeting or exercise between 

representatives of the owner or operator of the CCR unit and the local emergency responders.

(ii) Amendment of the plan. (A) The owner or operator of a CCR unit subject to the 

requirements of paragraph (a)(3)(i) of this section may amend the written EAP at any time 

provided the revised plan is placed in the facility’s operating record as required by § 

257.105(f)(6). The owner or operator must amend the written EAP whenever there is a change 

in conditions that would substantially affect the EAP in effect.

(B) The written EAP must be evaluated, at a minimum, every five years to ensure the 

information required in paragraph (a)(3)(i) of this section is accurate. As necessary, the EAP 

must be updated and a revised EAP placed in the facility’s operating record as required by § 

257.105(f)(6).

(iii) Changes in hazard potential classification. (A) If the owner or operator of a CCR

unit determines during a periodic hazard potential assessment that the CCR unit is no longer 
Document submitted to conclude E.O.12866 Review

641

classified as either a high hazard potential CCR surface impoundment or a significant hazard 

potential CCR surface impoundment, then the owner or operator of the CCR unit is no longer 

subject to the requirement to prepare and maintain a written EAP beginning on the date the 

periodic hazard potential assessment documentation is placed in the facility’s operating record as 

required by § 257.105(f)(5).

(B) If the owner or operator of a CCR unit classified as a low hazard potential CCR 

surface impoundment subsequently determines that the CCR unit is properly re-classified as 

either a high hazard potential CCR surface impoundment or a significant hazard potential CCR 

surface impoundment, then the owner or operator of the CCR unit must prepare a written EAP 

for the CCR unit as required by paragraph (a)(3)(i) of this section within six months of 

completing such periodic hazard potential assessment.

(iv) The owner or operator of the CCR unit must obtain a certification from a qualified 

professional engineer stating that the written EAP, and any subsequent amendment of the EAP, 

meets the requirements of paragraph (a)(3) of this section.

(v) Activation of the EAP. The EAP must be implemented once events or 

circumstances involving the CCR unit that represent a safety emergency are detected, including 

conditions identified during periodic structural stability assessments, annual inspections, and 

inspections by a qualified person.

(4) The CCR unit and surrounding areas must be designed, constructed, operated, and 

maintained with vegetated slopes of dikes not to exceed a height of 6 inches above the slope of 

the dike, except for slopes which are protected with an alternate form(s) of slope protection.

(b) The requirements of paragraphs (c) through (e) of this section apply to an owner 

or operator of an existing CCR surface impoundment that either:
Document submitted to conclude E.O.12866 Review

642

(1) Has a height of five feet or more and a storage volume of 20 acre-feet or more; or

(2) Has a height of 20 feet or more.

(c)(1) No later than [INSERT DATE 18 MONTHS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER], the owner or operator of the CCR unit 

must compile a history of construction, which shall contain, to the extent feasible, the 

information specified in paragraphs (c)(1)(i) through (c)(1)(xi) of this section.

(i) The name and address of the person(s) owning or operating the CCR unit; the 

name associated with the CCR unit; and the identification number of the CCR unit if one has 

been assigned by the state.

(ii) The location of the CCR unit identified on the most recent U.S. Geological 

Survey (USGS) 71⁄2 minute or 15 minute topographic quadrangle map, or a topographic map of 

equivalent scale if a USGS map is not available.

(iii) A statement of the purpose for which the CCR unit is being used.

(iv) The name and size in acres of the watershed within which the CCR unit is located.

(v) A description of the physical and engineering properties of the foundation and 

abutment materials on which the CCR unit is constructed.

(vi) A statement of the type, size, range, and physical and engineering properties of 

the materials used in constructing each zone or stage of the CCR unit; the method of site 

preparation and construction of each zone of the CCR unit; and the approximate dates of 

construction of each successive stage of construction of the CCR unit.

(vii) At a scale that details engineering structures and appurtenances relevant to the 

design, construction, operation, and maintenance of the CCR unit, detailed dimensional drawings 

of the CCR unit, including a plan view and cross sections of the length and width of the CCR 
Document submitted to conclude E.O.12866 Review

643

unit, showing all zones, foundation improvements, drainage provisions, spillways, diversion 

ditches, outlets, instrument locations, and slope protection, in addition to the normal operating 

pool surface elevation and the maximum pool surface elevation following peak discharge from 

the inflow design flood, the expected maximum depth of CCR within the CCR surface 

impoundment, and any identifiable natural or manmade features that could adversely affect 

operation of the CCR unit due to malfunction or mis-operation.

(viii) A description of the type, purpose, and location of existing instrumentation.

(ix) Area-capacity curves for the CCR unit.

(x) A description of each spillway and diversion design features and capacities and 

calculations used in their determination.

(xi) The construction specifications and provisions for surveillance, maintenance, and 

repair of the CCR unit.

(xii) Any record or knowledge of structural instability of the CCR unit.

(2) Changes to the history of construction. If there is a significant change to any 

information compiled under paragraph (c)(1) of this section, the owner or operator of the CCR 

unit must update the relevant information and place it in the facility’s operating record as 

required by § 257.105(f)(9).

(d) Periodic structural stability assessments. (1) The owner or operator of the CCR 

unit must conduct initial and periodic structural stability assessments and document whether the 

design, construction, operation, and maintenance of the CCR unit is consistent with recognized 

and generally accepted good engineering practices for the maximum volume of CCR and CCR 

wastewater which can be impounded therein. The assessment must, at a minimum, document 

whether the CCR unit has been designed, constructed, operated, and maintained with:
Document submitted to conclude E.O.12866 Review

644

(i) Stable foundations and abutments;

(ii) Adequate slope protection to protect against surface erosion, wave action, and 

adverse effects of sudden drawdown;

(iii) Dikes mechanically compacted to a density sufficient to withstand the range of 

loading conditions in the CCR unit;

(iv) Vegetated slopes of dikes and surrounding areas not to exceed a height of 6 inches 

above the slope of the dike, except for slopes which have an alternate form or forms of slope 

protection;

(v) A single spillway or a combination of spillways configured as specified in 

paragraph (d)(1)(v)(A) of this section. The combined capacity of all spillways must be designed, 

constructed, operated, and maintained to adequately manage flow during and following the peak 

discharge from the event specified in paragraph (d)(1)(v)(B) of this section.

(A) All spillways must be either:

(1) Of non-erodible construction and designed to carry sustained flows; or

(2) Earth- or grass-lined and designed to carry short-term, infrequent flows at nonerosive velocities where sustained flows are not expected.

(B) The combined capacity of all spillways must adequately manage flow during and 

following the peak discharge from a:

(1) Probable maximum flood (PMF) for a high hazard potential CCR surface 

impoundment; or

(2) 1000-year flood for a significant hazard potential CCR surface impoundment; or

(3) 100-year flood for a low hazard potential CCR surface impoundment. 
Document submitted to conclude E.O.12866 Review

645

(vi) Hydraulic structures underlying the base of the CCR unit or passing through the 

dike of the CCR unit that maintain structural integrity and are free of significant deterioration, 

deformation, distortion, bedding deficiencies, sedimentation, and debris which may negatively 

affect the operation of the hydraulic structure; and

(vii) For CCR units with downstream slopes which can be inundated by the pool of an 

adjacent water body, such as a river, stream or lake, downstream slopes that maintain structural 

stability during low pool of the adjacent water body or sudden drawdown of the adjacent water 

body.

(2) The periodic assessment described in paragraph (d)(1) of this section must 

identify any structural stability deficiencies associated with the CCR unit in addition to 

recommending corrective measures. If a deficiency or a release is identified during the periodic 

assessment, the owner or operator unit must remedy the deficiency or release as soon as feasible.

(3) The owner or operator of the CCR unit must obtain a certification from a qualified 

professional engineer stating that the initial assessment and each subsequent periodic assessment 

was conducted in accordance with the requirements of this section.

(e) Periodic safety factor assessments. (1) The owner or operator must conduct an 

initial and periodic safety factor assessments for each CCR unit and document whether the 

calculated factors of safety for each CCR unit achieve the minimum safety factors specified in 

paragraphs (e)(1)(i) through (e)(1)(iv) of this section for the critical cross section of the 

embankment. The critical cross section is the cross section anticipated to be the most susceptible 

of all cross sections to structural failure based on appropriate engineering considerations, 

including loading conditions. The safety factor assessments must be supported by appropriate 

engineering calculations.
Document submitted to conclude E.O.12866 Review

646

(i) The calculated static factor of safety under the long-term, maximum storage pool 

loading condition must equal or exceed 1.50.

(ii) The calculated static factor of safety under the maximum surcharge pool loading 

condition must equal or exceed 1.40.

(iii) The calculated seismic factor of safety must equal or exceed 1.00.

(iv) For dikes constructed of soils that have susceptibility to liquefaction, the 

calculated liquefaction factor of safety must equal or exceed 1.20.

(2) The owner or operator of the CCR unit must obtain a certification from a qualified 

professional engineer stating that the initial assessment and each subsequent periodic assessment 

specified in paragraph (e)(1) of this section meets the requirements of this section.

(f) Timeframes for periodic assessments. (1) Initial assessments. Except as 

provided by paragraph (f)(2) of this section, the owner or operator of the CCR unit must 

complete the initial assessments required by paragraphs (a)(2), (d), and (e) of this section no later 

than [INSERT DATE 18 MONTHS AFTER DATE OF PUBLICATION IN THE 

FEDERAL REGISTER]. The owner or operator has completed an initial assessment when the 

owner or operator has placed the assessment required by paragraphs (a)(2), (d), and (e) of this 

section in the facility’s operating record as required by § 257.105(f)(5), (f)(10), and (f)(12).

(2) Use of a previously completed assessment(s) in lieu of the initial assessment(s). 

The owner or operator of the CCR unit may elect to use a previously completed assessment to 

serve as the initial assessment required by paragraphs (a)(2), (d), and (e) of this section provided 

that the previously completed assessment(s):

(i) Was completed no earlier than 42 months prior to [INSERT DATE 18 

MONTHS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER]; and
Document submitted to conclude E.O.12866 Review

647

(ii) Meets the applicable requirements of paragraphs (a)(2), (d), and (e) of this 

section.

(3) Frequency for conducting periodic assessments. The owner or operator of the 

CCR unit must conduct and complete the assessments required by paragraphs (a)(2), (d), and (e) 

of this section every five years. The date of completing the initial assessment is the basis for 

establishing the deadline to complete the first subsequent assessment. If the owner or operator 

elects to use a previously completed assessment(s) in lieu of the initial assessment as provided by 

paragraph (f)(2) of this section, the date of the report for the previously completed assessment is 

the basis for establishing the deadline to complete the first subsequent assessment. The owner or 

operator may complete any required assessment prior to the required deadline provided the 

owner or operator places the completed assessment(s) into the facility’s operating record within a 

reasonable amount of time. In all cases, the deadline for completing subsequent assessments is 

based on the date of completing the previous assessment. For purposes of this paragraph, the 

owner or operator has completed an assessment when the relevant assessment(s) required by 

paragraphs (a)(2), (d), and (e) of this section has been placed in the facility’s operating record as 

required by § 257.105(f)(5), (f)(10), and (f)(12).

(4) Closure of the CCR unit. An owner or operator of a CCR unit who either fails to 

complete a timely safety factor assessment or fails to demonstrate minimum safety factors as 

required by paragraph (e) of this section is subject to the requirements of § 257.101(b)(2).

(g) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(f), the notification requirements specified in § 257.106(f), 

and the internet requirements specified in § 257.107(f).
Document submitted to conclude E.O.12866 Review

648

§ 257.74 Structural integrity criteria for new CCR surface impoundments and any lateral 

expansion of a CCR surface impoundment.

(a) The requirements of paragraphs (a)(1) through (a)(4) of this section apply to all 

new CCR surface impoundments and any lateral expansion of a CCR surface impoundment, 

except for those new CCR surface impoundments that are incised CCR units. If an incised CCR 

surface impoundment is subsequently modified (e.g., a dike is constructed) such that the CCR 

unit no longer meets the definition of an incised CCR unit, the CCR unit is subject to the 

requirements of paragraphs (a)(1) through (a)(4) of this section.

(1) No later than the initial receipt of CCR, the owner or operator of the CCR unit 

must place on or immediately adjacent to the CCR unit a permanent identification marker, at 

least six feet high showing the identification number of the CCR unit, if one has been assigned 

by the state, the name associated with the CCR unit and the name of the owner or operator of the 

CCR unit.

(2) Periodic hazard potential classification assessments. (i) The owner or operator of 

the CCR unit must conduct initial and periodic hazard potential classification assessments of the 

CCR unit according to the timeframes specified in paragraph (f) of this section. The owner or 

operator must document the hazard potential classification of each CCR unit as either a high 

hazard potential CCR surface impoundment, a significant hazard potential CCR surface 

impoundment, or a low hazard potential CCR surface impoundment. The owner or operator 

must also document the basis for each hazard potential classification.

(ii) The owner or operator of the CCR unit must obtain a certification from a qualified 

professional engineer stating that the initial hazard potential classification and each subsequent 
Document submitted to conclude E.O.12866 Review

649

periodic classification specified in paragraph (a)(2)(i) of this section was conducted in 

accordance with the requirements of this section.

(3) Emergency Action Plan (EAP). (i) Development of the plan. Prior to the initial 

receipt of CCR in the CCR unit, the owner or operator of a CCR unit determined to be either a 

high hazard potential CCR surface impoundment or a significant hazard potential CCR surface 

impoundment under paragraph (a)(2) of this section must prepare and maintain a written EAP. 

At a minimum, the EAP must:

(A) Define the events or circumstances involving the CCR unit that represent a safety 

emergency, along with a description of the procedures that will be followed to detect a safety 

emergency in a timely manner;

(B) Define responsible persons, their respective responsibilities, and notification 

procedures in the event of a safety emergency involving the CCR unit;

(C) Provide contact information of emergency responders;

(D) Include a map which delineates the downstream area which would be affected in 

the event of a CCR unit failure and a physical description of the CCR unit; and

(E) Include provisions for an annual face-to-face meeting or exercise between 

representatives of the owner or operator of the CCR unit and the local emergency responders.

(ii) Amendment of the plan. (A) The owner or operator of a CCR unit subject to the 

requirements of paragraph (a)(3)(i) of this section may amend the written EAP at any time 

provided the revised plan is placed in the facility’s operating record as required by § 

257.105(f)(6). The owner or operator must amend the written EAP whenever there is a change 

in conditions that would substantially affect the EAP in effect.
Document submitted to conclude E.O.12866 Review

650

(B) The written EAP must be evaluated, at a minimum, every five years to ensure the 

information required in paragraph (a)(3)(i) of this section is accurate. As necessary, the EAP 

must be updated and a revised EAP placed in the facility’s operating record as required by § 

257.105(f)(6).

(iii) Changes in hazard potential classification. (A) If the owner or operator of a CCR 

unit determines during a periodic hazard potential assessment that the CCR unit is no longer 

classified as either a high hazard potential CCR surface impoundment or a significant hazard 

potential CCR surface impoundment, then the owner or operator of the CCR unit is no longer 

subject to the requirement to prepare and maintain a written EAP beginning on the date the 

periodic hazard potential assessment documentation is placed in the facility’s operating record as 

required by § 257.105(f)(5).

(B) If the owner or operator of a CCR unit classified as a low hazard potential CCR 

surface impoundment subsequently determines that the CCR unit is properly re-classified as 

either a high hazard potential CCR surface impoundment or a significant hazard potential CCR 

surface impoundment, then the owner or operator of the CCR unit must prepare a written EAP 

for the CCR unit as required by paragraph (a)(3)(i) of this section within six months of 

completing such periodic hazard potential assessment.

(iv) The owner or operator of the CCR unit must obtain a certification from a qualified 

professional engineer stating that the written EAP, and any subsequent amendment of the EAP, 

meets the requirements of paragraph (a)(3) of this section.

(v) Activation of the EAP. The EAP must be implemented once events or 

circumstances involving the CCR unit that represent a safety emergency are detected, including 
Document submitted to conclude E.O.12866 Review

651

conditions identified during periodic structural stability assessments, annual inspections, and 

inspections by a qualified person.

(4) The CCR unit and surrounding areas must be designed, constructed, operated, and 

maintained with vegetated slopes of dikes not to exceed a height of 6 inches above the slope of 

the dike, except for slopes which are protected with an alternate form(s) of slope protection.

(b) The requirements of paragraphs (c) through (e) of this section apply to an owner 

or operator of a new CCR surface impoundment and any lateral expansion of a CCR surface 

impoundment that either:

(1) Has a height of five feet or more and a storage volume of 20 acre-feet or more; or

(2) Has a height of 20 feet or more.

(c) (1) No later than the initial receipt of CCR in the CCR unit, the owner or operator 

unit must compile the design and construction plans for the CCR unit, which must include, to the 

extent feasible, the information specified in paragraphs (c)(1)(i) through (c)(1)(xi) of this section.

(i) The name and address of the person(s) owning or operating the CCR unit; the 

name associated with the CCR unit; and the identification number of the CCR unit if one has 

been assigned by the state.

(ii) The location of the CCR unit identified on the most recent U.S. Geological 

Survey (USGS) 71⁄2 minute or 15 minute topographic quadrangle map, or a topographic map of 

equivalent scale if a USGS map is not available.

(iii) A statement of the purpose for which the CCR unit is being used.

(iv) The name and size in acres of the watershed within which the CCR unit is located.

(v) A description of the physical and engineering properties of the foundation and 

abutment materials on which the CCR unit is constructed.
Document submitted to conclude E.O.12866 Review

652

(vi) A statement of the type, size, range, and physical and engineering properties of 

the materials used in constructing each zone or stage of the CCR unit; the method of site 

preparation and construction of each zone of the CCR unit; and the dates of construction of each 

successive stage of construction of the CCR unit.

(vii) At a scale that details engineering structures and appurtenances relevant to the 

design, construction, operation, and maintenance of the CCR unit, detailed dimensional drawings 

of the CCR unit, including a plan view and cross sections of the length and width of the CCR 

unit, showing all zones, foundation improvements, drainage provisions, spillways, diversion 

ditches, outlets, instrument locations, and slope protection, in addition to the normal operating 

pool surface elevation and the maximum pool surface elevation following peak discharge from 

the inflow design flood, the expected maximum depth of CCR within the CCR surface 

impoundment, and any identifiable natural or manmade features that could adversely affect 

operation of the CCR unit due to malfunction or mis-operation.

(viii) A description of the type, purpose, and location of existing instrumentation.

(ix) Area-capacity curves for the CCR unit. 

(x) A description of each spillway and diversion design features and capacities and 

calculations used in their determination.

(xi) The construction specifications and provisions for surveillance, maintenance, and 

repair of the CCR unit.

(xii) Any record or knowledge of structural instability of the CCR unit.

(2) Changes in the design and construction. If there is a significant change to any 

information compiled under paragraph (c)(1) of this section, the owner or operator of the CCR 
Document submitted to conclude E.O.12866 Review

653

unit must update the relevant information and place it in the facility’s operating record as 

required by § 257.105(f)(13).

(d) Periodic structural stability assessments. (1) The owner or operator of the CCR 

unit must conduct initial and periodic structural stability assessments and document whether the 

design, construction, operation, and maintenance of the CCR unit is consistent with recognized 

and generally accepted good engineering practices for the maximum volume of CCR and CCR 

wastewater which can be impounded therein. The assessment must, at a minimum, document 

whether the CCR unit has been designed, constructed, operated, and maintained with:

(i) Stable foundations and abutments;

(ii) Adequate slope protection to protect against surface erosion, wave action, and 

adverse effects of sudden drawdown;

(iii) Dikes mechanically compacted to a density sufficient to withstand the range of 

loading conditions in the CCR unit;

(iv) Vegetated slopes of dikes and surrounding areas not to exceed a height of 6 inches 

above the slope of the dike, except for slopes which have an alternate form or forms of slope 

protection;

(v) A single spillway or a combination of spillways configured as specified in 

paragraph (d)(1)(v)(A) of this section. The combined capacity of all spillways must be designed, 

constructed, operated, and maintained to adequately manage flow during and following the peak 

discharge from the event specified in paragraph (d)(1)(v)(B) of this section.

(A) All spillways must be either:

(1) Of non-erodible construction and designed to carry sustained flows; or
Document submitted to conclude E.O.12866 Review

654

(2) Earth- or grass-lined and designed to carry short-term, infrequent flows at nonerosive velocities where sustained flows are not expected.

(B) The combined capacity of all spillways must adequately manage flow during and 

following the peak discharge from a:

(1) Probable maximum flood (PMF) for a high hazard potential CCR surface 

impoundment; or

(2) 1000-year flood for a significant hazard potential CCR surface impoundment; or

(3) 100-year flood for a low hazard potential CCR surface impoundment. 

(vi) Hydraulic structures underlying the base of the CCR unit or passing through the 

dike of the CCR unit that maintain structural integrity and are free of significant deterioration, 

deformation, distortion, bedding deficiencies, sedimentation, and debris which may negatively 

affect the operation of the hydraulic structure; and

(vii) For CCR units with downstream slopes which can be inundated by the pool of an 

adjacent water body, such as a river, stream or lake, downstream slopes that maintain structural 

stability during low pool of the adjacent water body or sudden drawdown of the adjacent water 

body.

(2) The periodic assessment described in paragraph (d)(1) of this section must 

identify any structural stability deficiencies associated with the CCR unit in addition to 

recommending corrective measures. If a deficiency or a release is identified during the periodic 

assessment, the owner or operator unit must remedy the deficiency or release as soon as feasible.

(3) The owner or operator of the CCR unit must obtain a certification from a qualified 

professional engineer stating that the initial assessment and each subsequent periodic assessment 

was conducted in accordance with the requirements of this section.
Document submitted to conclude E.O.12866 Review

655

(e) Periodic safety factor assessments. (1) The owner or operator must conduct an 

initial and periodic safety factor assessments for each CCR unit and document whether the 

calculated factors of safety for each CCR unit achieve the minimum safety factors specified in 

paragraphs (e)(1)(i) through (e)(1)(v) of this section for the critical cross section of the 

embankment. The critical cross section is the cross section anticipated to be the most susceptible 

of all cross sections to structural failure based on appropriate engineering considerations, 

including loading conditions. The safety factor assessments must be supported by appropriate 

engineering calculations.

(i) The calculated static factor of safety under the end-of-construction loading 

condition must equal or exceed 1.30. The assessment of this loading condition is only required 

for the initial safety factor assessment and is not required for subsequent assessments.

(ii) The calculated static factor of safety under the long-term, maximum storage pool 

loading condition must equal or exceed 1.50.

(iii) The calculated static factor of safety under the maximum surcharge pool loading 

condition must equal or exceed 1.40.

(iv) The calculated seismic factor of safety must equal or exceed 1.00.

(v) For dikes constructed of soils that have susceptibility to liquefaction, the 

calculated liquefaction factor of safety must equal or exceed 1.20.

(2) The owner or operator of the CCR unit must obtain a certification from a qualified 

professional engineer stating that the initial assessment and each subsequent periodic assessment 

specified in paragraph (e)(1) of this section meets the requirements of this section.

(f) Timeframes for periodic assessments. (1) Initial assessments. Except as provided 

by paragraph (f)(2) of this section, the owner or operator of the CCR unit must complete the 
Document submitted to conclude E.O.12866 Review

656

initial assessments required by paragraphs (a)(2), (d), and (e) of this section prior to the initial 

receipt of CCR in the unit. The owner or operator has completed an initial assessment when the 

owner or operator has placed the assessment required by paragraphs (a)(2), (d), and (e) of this 

section in the facility’s operating record as required by § 257.105(f)(5), (f)(10), and (f)(12).

(2) Frequency for conducting periodic assessments. The owner or operator of the 

CCR unit must conduct and complete the assessments required by paragraphs (a)(2), (d), and (e) 

of this section every five years. The date of completing the initial assessment is the basis for 

establishing the deadline to complete the first subsequent assessment. The owner or operator 

may complete any required assessment prior to the required deadline provided the owner or 

operator places the completed assessment(s) into the facility’s operating record within a 

reasonable amount of time. In all cases, the deadline for completing subsequent assessments is 

based on the date of completing the previous assessment. For purposes of this paragraph, the 

owner or operator has completed an assessment when the relevant assessment(s) required by 

paragraphs (a)(2), (d), and (e) of this section has been placed in the facility’s operating record as 

required by § 257.105(f)(5), (f)(10), and (f)(12).

(3) Failure to document minimum safety factors during the initial assessment. Until 

the date an owner or operator of a CCR unit documents that the calculated factors of safety 

achieve the minimum safety factors specified in paragraphs (e)(1)(i) through (e)(1)(v) of this 

section, the owner or operator is prohibited from placing CCR in such unit.

(4) Closure of the CCR unit. An owner or operator of a CCR unit who either fails to 

complete a timely periodic safety factor assessment or fails to demonstrate minimum safety 

factors as required by paragraph (e) of this section is subject to the requirements of § 257.101(c).
Document submitted to conclude E.O.12866 Review

657

(g) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(f), the notification requirements specified in § 257.106(f), 

and the internet requirements specified in § 257.107(f).

Operating Criteria

§ 257.80 Air criteria.

(a) The owner or operator of a CCR landfill, CCR surface impoundment, or any 

lateral expansion of a CCR unit must adopt measures that will effectively minimize CCR from 

becoming airborne at the facility, including CCR fugitive dust originating from CCR units, 

roads, and other CCR management and material handling activities.

(b) CCR fugitive dust control plan. The owner or operator of the CCR unit must 

prepare and operate in accordance with a CCR fugitive dust control plan as specified in 

paragraphs (b)(1) through (b)(7) of this section. This requirement applies in addition to, not in 

place of, any applicable standards under the Occupational Safety and Health Act.

(1) The CCR fugitive dust control plan must identify and describe the CCR fugitive 

dust control measures the owner or operator will use to minimize CCR from becoming airborne 

at the facility. The owner or operator must select, and include in the CCR fugitive dust control 

plan, the CCR fugitive dust control measures that are most appropriate for site conditions, along 

with an explanation of how the measures selected are applicable and appropriate for site 

conditions. Examples of control measures that may be appropriate include: locating CCR inside 

an enclosure or partial enclosure; operating a water spray or fogging system; reducing fall 

distances at material drop points; using wind barriers, compaction, or vegetative covers; 

establishing and enforcing reduced vehicle speed limits; paving and sweeping roads; covering 
Document submitted to conclude E.O.12866 Review

658

trucks transporting CCR; reducing or halting operations during high wind events; or applying a 

daily cover.

(2) If the owner or operator operates a CCR landfill or any lateral expansion of a 

CCR landfill, the CCR fugitive dust control plan must include procedures to emplace CCR as 

conditioned CCR. Conditioned CCR means wetting CCR with water to a moisture content that 

will prevent wind dispersal, but will not result in free liquids. In lieu of water, CCR conditioning 

may be accomplished with an appropriate chemical dust suppression agent.

(3) The CCR fugitive dust control plan must include procedures to log citizen 

complaints received by the owner or operator involving CCR fugitive dust events at the facility.

(4) The CCR fugitive dust control plan must include a description of the procedures 

the owner or operator will follow to periodically assess the effectiveness of the control plan.

(5) The owner or operator of a CCR unit must prepare an initial CCR fugitive dust 

control plan for the facility no later than [INSERT DATE 6 MONTHS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER], or by initial receipt of CCR in any CCR 

unit at the facility if the owner or operator becomes subject to this subpart after [INSERT DATE 

6 MONTHS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER]. The 

owner or operator has completed the initial CCR fugitive dust control plan when the plan has 

been placed in the facility’s operating record as required by § 257.105(g)(1).

(6) Amendment of the plan. The owner or operator of a CCR unit subject to the 

requirements of this section may amend the written CCR fugitive dust control plan at any time 

provided the revised plan is placed in the facility’s operating record as required by § 

257.105(g)(1). The owner or operator must amend the written plan whenever there is a change 
Document submitted to conclude E.O.12866 Review

659

in conditions that would substantially affect the written plan in effect, such as the construction 

and operation of a new CCR unit.

(7) The owner or operator must obtain a certification from a qualified professional 

engineer that the initial CCR fugitive dust control plan, or any subsequent amendment of it, 

meets the requirements of this section.

(c) Annual CCR fugitive dust control report. The owner or operator of a CCR unit 

must prepare an annual CCR fugitive dust control report that includes a description of the actions 

taken by the owner or operator to control CCR fugitive dust, a record of all citizen complaints, 

and a summary of any corrective measures taken. The initial annual report must be completed 

no later than 14 months after placing the initial CCR fugitive dust control plan in the facility’s 

operating record. The deadline for completing a subsequent report is one year after the date of 

completing the previous report. For purposes of this paragraph, the owner or operator has 

completed the annual CCR fugitive dust control report when the plan has been placed in the 

facility’s operating record as required by § 257.105(g)(2).

(d) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(g), the notification requirements specified in § 257.106(g), 

and the internet requirements specified in § 257.107(g).

§ 257.81 Run-on and run-off controls for CCR landfills.

(a) The owner or operator of an existing or new CCR landfill or any lateral expansion 

of a CCR landfill must design, construct, operate, and maintain:

(1) A run-on control system to prevent flow onto the active portion of the CCR unit 

during the peak discharge from a 24-hour, 25-year storm; and
Document submitted to conclude E.O.12866 Review

660

(2) A run-off control system from the active portion of the CCR unit to collect and 

control at least the water volume resulting from a 24-hour, 25-year storm.

(b) Run-off from the active portion of the CCR unit must be handled in accordance 

with the surface water requirements under § 257.3-3.

(c) Run-on and run-off control system plan. (1) Content of the plan. The owner or 

operator must prepare initial and periodic run-on and run-off control system plans for the CCR 

unit according to the timeframes specified in paragraphs (c)(3) and (c)(4) of this section. These 

plans must document how the run-on and run-off control systems have been designed and 

constructed to meet the applicable requirements of this section. Each plan must be supported by 

appropriate engineering calculations. The owner or operator has completed the initial run-on and 

run-off control system plan when the plan has been placed in the facility’s operating record as 

required by § 257.105(g)(3).

(2) Amendment of the plan. The owner or operator may amend the written run-on 

and run-off control system plan at any time provided the revised plan is placed in the facility’s 

operating record as required by § 257.105(g)(3). The owner or operator must amend the written 

run-on and run-off control system plan whenever there is a change in conditions that would 

substantially affect the written plan in effect.

(3) Timeframes for preparing the initial plan. (i) Existing CCR landfills. The owner 

or operator of the CCR unit must prepare the initial run-on and run-off control system plan no 

later than [INSERT DATE 18 MONTHS AFTER DATE OF PUBLICATION IN THE 

FEDERAL REGISTER]. 
Document submitted to conclude E.O.12866 Review

661

(ii) New CCR landfills and any lateral expansion of a CCR landfill. The owner or 

operator must prepare the initial run-on and run-off control system plan no later than the date of 

initial receipt of CCR in the CCR unit.

(4) Frequency for revising the plan. The owner or operator of the CCR unit must 

prepare periodic run-on and run-off control system plans required by paragraph (c)(1) of this 

section every five years. The date of completing the initial plan is the basis for establishing the 

deadline to complete the first subsequent plan. The owner or operator may complete any 

required plan prior to the required deadline provided the owner or operator places the completed 

plan into the facility’s operating record within a reasonable amount of time. In all cases, the 

deadline for completing a subsequent plan is based on the date of completing the previous plan. 

For purposes of this paragraph, the owner or operator has completed a periodic run-on and runoff control system plan when the plan has been placed in the facility’s operating record as 

required by § 257.105(g)(3).

(5) The owner or operator must obtain a certification from a qualified professional 

engineer stating that the initial and periodic run-on and run-off control system plans meet the 

requirements of this section.

(d) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(g), the notification requirements specified in § 257.106(g), 

and the internet requirements specified in § 257.107(g).

§ 257.82 Hydrologic and hydraulic capacity requirements for CCR surface 

impoundments. 
Document submitted to conclude E.O.12866 Review

662

(a) The owner or operator of an existing or new CCR surface impoundment or any 

lateral expansion of a CCR surface impoundment must design, construct, operate, and maintain 

an inflow design flood control system as specified in paragraphs (a)(1) and (a)(2) of this section.

(1) The inflow design flood control system must adequately manage flow into the 

CCR unit during and following the peak discharge of the inflow design flood specified in 

paragraph (a)(3) of this section.

(2) The inflow design flood control system must adequately manage flow from the 

CCR unit to collect and control the peak discharge resulting from the inflow design flood 

specified in paragraph (a)(3) of this section.

(3) The inflow design flood is:

(i) For a high hazard potential CCR surface impoundment, as determined under § 

257.73(a)(2) or § 257.74(a)(2), the probable maximum flood;

(ii) For a significant hazard potential CCR surface impoundment, as determined 

under § 257.73(a)(2) or § 257.74(a)(2), the 1,000-year flood;

(iii) For a low hazard potential CCR surface impoundment, as determined under § 

257.73(a)(2) or § 257.74(a)(2), the 100-year flood; or

(iv) For an incised CCR surface impoundment, the 25-year flood.

(b) Discharge from the CCR unit must be handled in accordance with the surface 

water requirements under § 257.3-3.

(c) Inflow design flood control system plan. (1) Content of the plan. The owner or 

operator must prepare initial and periodic inflow design flood control system plans for the CCR 

unit according to the timeframes specified in paragraphs (c)(3) and (c)(4) of this section. These 

plans must document how the inflow design flood control system has been designed and 
Document submitted to conclude E.O.12866 Review

663

constructed to meet the requirements of this section. Each plan must be supported by appropriate 

engineering calculations. The owner or operator of the CCR unit has completed the inflow 

design flood control system plan when the plan has been placed in the facility’s operating record 

as required by § 257.105(g)(4).

(2) Amendment of the plan. The owner or operator of the CCR unit may amend the 

written inflow design flood control system plan at any time provided the revised plan is placed in 

the facility’s operating record as required by § 257.105(g)(4). The owner or operator must 

amend the written inflow design flood control system plan whenever there is a change in 

conditions that would substantially affect the written plan in effect.

(3) Timeframes for preparing the initial plan. (i) Existing CCR surface 

impoundments. The owner or operator of the CCR unit must prepare the initial inflow design 

flood control system plan no later than [INSERT DATE 18 MONTHS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER]. 

(ii) New CCR surface impoundments and any lateral expansion of a CCR surface 

impoundment. The owner or operator must prepare the initial inflow design flood control system 

plan no later than the date of initial receipt of CCR in the CCR unit.

(4) Frequency for revising the plan. The owner or operator must prepare periodic 

inflow design flood control system plans required by paragraph (c)(1) of this section every five 

years. The date of completing the initial plan is the basis for establishing the deadline to 

complete the first periodic plan. The owner or operator may complete any required plan prior to 

the required deadline provided the owner or operator places the completed plan into the facility’s 

operating record within a reasonable amount of time. In all cases, the deadline for completing a 

subsequent plan is based on the date of completing the previous plan. For purposes of this 
Document submitted to conclude E.O.12866 Review

664

paragraph, the owner or operator has completed an inflow design flood control system plan when 

the plan has been placed in the facility’s operating record as required by § 257.105(g)(4).

(5) The owner or operator must obtain a certification from a qualified professional 

engineer stating that the initial and periodic inflow design flood control system plans meet the 

requirements of this section.

(d) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(g), the notification requirements specified in § 257.106(g), 

and the internet requirements specified in § 257.107(g).

§ 257.83 Inspection requirements for CCR surface impoundments.

(a) Inspections by a qualified person. (1) All CCR surface impoundments and any 

lateral expansion of a CCR surface impoundment must be examined by a qualified person as 

follows:

(i) At intervals not exceeding 7 days, inspect for any appearances of actual or 

potential structural weakness and other conditions which are disrupting or have the potential to 

disrupt the operation or safety of the CCR unit;

(ii) At intervals not exceeding 7 days, inspect the discharge of all outlets of hydraulic 

structures which pass underneath the base of the surface impoundment or through the dike of the 

CCR unit for abnormal discoloration, flow or discharge of debris or sediment; and

(iii) At intervals not exceeding 30 days, monitor all CCR unit instrumentation.

(iv) The results of the inspection by a qualified person must be recorded in the 

facility’s operating record as required by § 257.105(g)(5).

(2) Timeframes for inspections by a qualified person. (i) Existing CCR surface 

impoundments. The owner or operator of the CCR unit must initiate the inspections required 
Document submitted to conclude E.O.12866 Review

665

under paragraph (a) of this section no later than [INSERT DATE 6 MONTHS AFTER DATE 

OF PUBLICATION IN THE FEDERAL REGISTER].

(ii) New CCR surface impoundments and any lateral expansion of a CCR surface 

impoundment. The owner or operator of the CCR unit must initiate the inspections required 

under paragraph (a) of this section upon initial receipt of CCR by the CCR unit.

(b) Annual inspections by a qualified professional engineer. (1) If the existing or new 

CCR surface impoundment or any lateral expansion of the CCR surface impoundment is subject 

to the periodic structural stability assessment requirements under § 257.73(d) or § 257.74(d), the 

CCR unit must additionally be inspected on a periodic basis by a qualified professional engineer 

to ensure that the design, construction, operation, and maintenance of the CCR unit is consistent 

with recognized and generally accepted good engineering standards. The inspection must, at a 

minimum, include:

(i) A review of available information regarding the status and condition of the CCR 

unit, including, but not limited to, files available in the operating record (e.g., CCR unit design 

and construction information required by §§ 257.73(c)(1) and 257.74(c)(1), previous periodic 

structural stability assessments required under §§ 257.73(d) and 257.74(d), the results of 

inspections by a qualified person, and results of previous annual inspections);

(ii) A visual inspection of the CCR unit to identify signs of distress or malfunction of 

the CCR unit and appurtenant structures; and

(iii) A visual inspection of any hydraulic structures underlying the base of the CCR 

unit or passing through the dike of the CCR unit for structural integrity and continued safe and 

reliable operation.
Document submitted to conclude E.O.12866 Review

666

(2) Inspection report. The qualified professional engineer must prepare a report 

following each inspection that addresses the following:

(i) Any changes in geometry of the impounding structure since the previous annual 

inspection;

(ii) The location and type of existing instrumentation and the maximum recorded 

readings of each instrument since the previous annual inspection;

(iii) The approximate minimum, maximum, and present depth and elevation of the 

impounded water and CCR since the previous annual inspection;

(iv) The storage capacity of the impounding structure at the time of the inspection;

(v) The approximate volume of the impounded water and CCR at the time of the 

inspection;

(vi) Any appearances of an actual or potential structural weakness of the CCR unit, in 

addition to any existing conditions that are disrupting or have the potential to disrupt the 

operation and safety of the CCR unit and appurtenant structures; and

(vii) Any other change(s) which may have affected the stability or operation of the 

impounding structure since the previous annual inspection.

(3) Timeframes for conducting the initial inspection. (i) Existing CCR surface 

impoundments. The owner or operator of the CCR unit must complete the initial inspection 

required by paragraphs (b)(1) and (b)(2) of this section no later than [INSERT DATE 9 

MONTHS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER].

(ii) New CCR surface impoundments and any lateral expansion of a CCR surface 

impoundment. The owner or operator of the CCR unit must complete the initial annual 
Document submitted to conclude E.O.12866 Review

667

inspection required by paragraphs (b)(1) and (b)(2) of this section is completed no later than 14 

months following the date of initial receipt of CCR in the CCR unit.

(4) Frequency of inspections. (i) Except as provided for in paragraph (b)(4)(ii) of this 

section, the owner or operator of the CCR unit must conduct the inspection required by 

paragraphs (b)(1) and (b)(2) of this section on an annual basis. The date of completing the initial 

inspection report is the basis for establishing the deadline to complete the first subsequent 

inspection. Any required inspection may be conducted prior to the required deadline provided 

the owner or operator places the completed inspection report into the facility’s operating record 

within a reasonable amount of time. In all cases, the deadline for completing subsequent 

inspection reports is based on the date of completing the previous inspection report. For 

purposes of this section, the owner or operator has completed an inspection when the inspection 

report has been placed in the facility’s operating record as required by § 257.105(g)(6).

(ii) In any calendar year in which both the periodic inspection by a qualified 

professional engineer and the quinquennial (occurring every 5 years) structural stability 

assessment by a qualified professional engineer required by §§ 257.73(d) and 257.74(d) are 

required to be completed, the annual inspection is not required, provided the structural stability 

assessment is completed during the calendar year. If the annual inspection is not conducted in a 

year as provided by this paragraph, the deadline for completing the next annual inspection is one 

year from the date of completing the quinquennial structural stability assessment.

(5) If a deficiency or release is identified during an inspection, the owner or operator 

must remedy the deficiency or release as soon as feasible. 
Document submitted to conclude E.O.12866 Review

668

(c) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(g), the notification requirements specified in § 257.106(g), 

and the internet requirements specified in § 257.107(g).

257.84 Inspection requirements for CCR landfills.

(a) Inspections by a qualified person. (1) All CCR landfills and any lateral expansion 

of a CCR landfill must be examined by a qualified person as follows:

(i) At intervals not exceeding 7 days, inspect for any appearances of actual or 

potential structural weakness and other conditions which are disrupting or have the potential to 

disrupt the operation or safety of the CCR unit; and

(ii) The results of the inspection by a qualified person must be recorded in the 

facility’s operating record as required by § 257.105(g)(8).

(2) Timeframes for inspections by a qualified person. (i) Existing CCR surface 

impoundments. The owner or operator of the CCR unit must initiate the inspections required 

under paragraph (a) of this section no later than [INSERT DATE 6 MONTHS AFTER DATE 

OF PUBLICATION IN THE FEDERAL REGISTER].

(ii) New CCR surface impoundments and any lateral expansion of a CCR surface 

impoundment. The owner or operator of the CCR unit must initiate the inspections required 

under paragraph (a) of this section upon initial receipt of CCR by the CCR unit.

(b) Annual inspections by a qualified professional engineer. (1) Existing and new 

CCR landfills and any lateral expansion of a CCR landfill must be inspected on a periodic basis 

by a qualified professional engineer to ensure that the design, construction, operation, and 

maintenance of the CCR unit is consistent with recognized and generally accepted good 

engineering standards. The inspection must, at a minimum, include:
Document submitted to conclude E.O.12866 Review

669

(i) A review of available information regarding the status and condition of the CCR 

unit, including, but not limited to, files available in the operating record (e.g., the results of 

inspections by a qualified person, and results of previous annual inspections); and

(ii) A visual inspection of the CCR unit to identify signs of distress or malfunction of 

the CCR unit.

(2) Inspection report. The qualified professional engineer must prepare a report 

following each inspection that addresses the following:

(i) Any changes in geometry of the structure since the previous annual inspection;

(ii) The approximate volume of CCR at the time of the inspection;

(iii) Any appearances of an actual or potential structural weakness of the CCR unit, in 

addition to any existing conditions that are disrupting or have the potential to disrupt the 

operation and safety of the CCR unit; and

(iv) Any other change(s) which may have affected the stability or operation of the 

CCR unit since the previous annual inspection.

(3) Timeframes for conducting the initial inspection. (i) Existing CCR landfills. The 

owner or operator of the CCR unit must complete the initial inspection required by paragraphs 

(b)(1) and (b)(2) of this section no later than [INSERT DATE 9 MONTHS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER].

(ii) New CCR landfills and any lateral expansion of a CCR landfill. The owner or 

operator of the CCR unit must complete the initial annual inspection required by paragraphs

(b)(1) and (b)(2) of this section no later than 14 months following the date of initial receipt of 

CCR in the CCR unit.
Document submitted to conclude E.O.12866 Review

670

(4) Frequency of inspections. The owner or operator of the CCR unit must conduct 

the inspection required by paragraphs (b)(1) and (b)(2) of this section on an annual basis. The 

date of completing the initial inspection report is the basis for establishing the deadline to 

complete the first subsequent inspection. Any required inspection may be conducted prior to the 

required deadline provided the owner or operator places the completed inspection report into the 

facility’s operating record within a reasonable amount of time. In all cases, the deadline for 

completing subsequent inspection reports is based on the date of completing the previous 

inspection report. For purposes of this section, the owner or operator has completed an 

inspection when the inspection report has been placed in the facility’s operating record as 

required by § 257.105(g)(9).

(5) If a deficiency or release is identified during an inspection, the owner or operator 

must remedy the deficiency or release as soon as feasible. 

(c) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(g), the notification requirements specified in § 257.106(g), 

and the internet requirements specified in § 257.107(g).

Groundwater Monitoring and Corrective Action

§ 257.90 Applicability.

(a) Except as provided for in § 257.100 for inactive CCR surface impoundments, all 

CCR landfills, CCR surface impoundments, and lateral expansions of CCR units are subject to 

the groundwater monitoring and corrective action requirements under §§ 257.90 through 257.98.

(b) Initial timeframes. (1) Existing CCR landfills and existing CCR surface 

impoundments. No later than [INSERT DATE 30 MONTHS AFTER DATE OF 
Document submitted to conclude E.O.12866 Review

671

PUBLICATION IN THE FEDERAL REGISTER], the owner or operator of the CCR unit 

must be in compliance with the following groundwater monitoring requirements:

(i) Install the groundwater monitoring system as required by § 257.91;

(ii) Develop the groundwater sampling and analysis program to include selection of 

the statistical procedures to be used for evaluating groundwater monitoring data as required by § 

257.93;

(iii) Initiate the detection monitoring program to include obtaining a minimum of eight 

independent samples for each background and downgradient well as required by § 257.94(b); 

and

(iv) Begin evaluating the groundwater monitoring data for statistically significant 

increases over background levels for the constituents listed in Appendix III of this part as 

required by § 257.94.

(2) New CCR landfills, new CCR surface impoundments, and all lateral expansions 

of CCR units. Prior to initial receipt of CCR by the CCR unit, the owner or operator must be in 

compliance with the groundwater monitoring requirements specified in paragraph (b)(1)(i) and 

(b)(1)(ii) of this section. In addition, the owner or operator of the CCR unit must initiate the 

detection monitoring program to include obtaining a minimum of eight independent samples for 

each background well as required by § 257.94(b).

(c) Once a groundwater monitoring system and groundwater monitoring program has 

been established at the CCR unit as required by this subpart, the owner or operator must conduct 

groundwater monitoring and, if necessary, corrective action throughout the active life and postclosure care period of the CCR unit.
Document submitted to conclude E.O.12866 Review

672

(d) In the event of a release from a CCR unit, the owner or operator must 

immediately take all necessary measures to control the source(s) of releases so as to reduce or 

eliminate, to the maximum extent feasible, further releases of contaminants into the environment. 

The owner or operator of the CCR unit must comply with all applicable requirements in §§ 

257.96, 257.97, and 257.98.

(e) Annual groundwater monitoring and corrective action report. For existing CCR 

landfills and existing CCR surface impoundments, no later than January 31, 2018, and annually 

thereafter, the owner and operator must prepare an annual groundwater monitoring and 

corrective action report. For new CCR landfills, new CCR surface impoundments, and all lateral 

expansions of CCR units, the owner and operator must prepare the initial annual groundwater 

monitoring and corrective action report no later than January 31 of the year following the 

calendar year a groundwater monitoring system has been established for such CCR unit as 

required by this subpart, and annually thereafter. For the preceding calendar year, the annual 

report must document the status of the groundwater monitoring and corrective action program 

for the CCR unit, summarize key actions completed, describe any problems encountered, discuss 

actions to resolve the problems, and project key activities for the upcoming year. For purposes 

of this section, the owner or operator has prepared the annual report when the report is placed in 

the facility’s operating record as required by § 257.105(h)(1). At a minimum, the annual 

groundwater monitoring and corrective action report must contain the following information, to 

the extent available:

(1) A map, aerial image, or diagram showing the CCR unit and all background (or 

upgradient) and downgradient monitoring wells, to include the well identification numbers, that 

are part of the groundwater monitoring program for the CCR unit;
Document submitted to conclude E.O.12866 Review

673

(2) Identification of any monitoring wells that were installed or decommissioned 

during the preceding year, along with a narrative description of why those actions were taken; 

(3) A summary including the number of groundwater samples that were collected for 

analysis for each background and downgradient well, the dates the samples were collected, and 

whether the sample was required by the detection monitoring or assessment monitoring 

programs;

(4) A narrative discussion of any transition between monitoring programs (e.g., the 

date and circumstances for transitioning from detection monitoring to assessment monitoring in 

addition to identifying the constituent(s) detected at a statistically significant increase over 

background levels); and

(5) Other information required to be included in the annual report as specified in §§ 

257.90 through 257.98.

(f) The owner or operator of the CCR unit must comply with the 

recordkeeping requirements specified in § 257.105(h), the notification requirements specified in 

§ 257.106(h), and the internet requirements specified in § 257.107(h).

§ 257.91 Groundwater monitoring systems.

(a) Performance standard. The owner or operator of a CCR unit must install a 

groundwater monitoring system that consists of a sufficient number of wells, installed at 

appropriate locations and depths, to yield groundwater samples from the uppermost aquifer that:

(1) Accurately represent the quality of background groundwater that has not been 

affected by leakage from a CCR unit. A determination of background quality may include 

sampling of wells that are not hydraulically upgradient of the CCR management area where:
Document submitted to conclude E.O.12866 Review

674

(i) Hydrogeologic conditions do not allow the owner or operator of the CCR unit to 

determine what wells are hydraulically upgradient; or

(ii) Sampling at other wells will provide an indication of background groundwater 

quality that is as representative or more representative than that provided by the upgradient 

wells; and

(2) Accurately represent the quality of groundwater passing the waste boundary of 

the CCR unit. The downgradient monitoring system must be installed at the waste boundary that 

ensures detection of groundwater contamination in the uppermost aquifer. All potential 

contaminant pathways must be monitored.

(b) The number, spacing, and depths of monitoring systems shall be determined 

based upon site-specific technical information that must include thorough characterization of:

(1) Aquifer thickness, groundwater flow rate, groundwater flow direction including 

seasonal and temporal fluctuations in groundwater flow; and

(2) Saturated and unsaturated geologic units and fill materials overlying the 

uppermost aquifer, materials comprising the uppermost aquifer, and materials comprising the 

confining unit defining the lower boundary of the uppermost aquifer, including, but not limited 

to, thicknesses, stratigraphy, lithology, hydraulic conductivities, porosities and effective 

porosities.

(c) The groundwater monitoring system must include the minimum number of 

monitoring wells necessary to meet the performance standards specified in paragraph (a) of this 

section, based on the site-specific information specified in paragraph (b) of this section. The 

groundwater monitoring system must contain:

(1) A minimum of one upgradient and three downgradient monitoring wells; and
Document submitted to conclude E.O.12866 Review

675

(2) Additional monitoring wells as necessary to accurately represent the quality of 

background groundwater that has not been affected by leakage from the CCR unit and the quality 

of groundwater passing the waste boundary of the CCR unit.

(d) The owner or operator of multiple CCR units may install a multiunit groundwater 

monitoring system instead of separate groundwater monitoring systems for each CCR unit.

(1) The multiunit groundwater monitoring system must be equally as capable of 

detecting monitored constituents at the waste boundary of the CCR unit as the individual 

groundwater monitoring system specified in paragraphs (a) through (c) of this section for each 

CCR unit based on the following factors:

(i) Number, spacing, and orientation of each CCR unit;

(ii) Hydrogeologic setting;

(iii) Site history; and

(iv) Engineering design of the CCR unit.

(2) If the owner or operator elects to install a multiunit groundwater monitoring 

system, and if the multiunit system includes at least one existing unlined CCR surface 

impoundment as determined by § 257.71(a), and if at any time after [INSERT DATE 6 

MONTHS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER] the owner 

or operator determines in any sampling event that the concentrations of one or more constituents 

listed in Appendix IV to this part are detected at statistically significant levels above the 

groundwater protection standard established under § 257.95(h) for the multiunit system, then all 

unlined CCR surface impoundments comprising the multiunit groundwater monitoring system 

are subject to the closure requirements under § 257.101(a).
Document submitted to conclude E.O.12866 Review

676

(e) Monitoring wells must be cased in a manner that maintains the integrity of the 

monitoring well bore hole. This casing must be screened or perforated and packed with gravel or 

sand, where necessary, to enable collection of groundwater samples. The annular space (i.e., the 

space between the bore hole and well casing) above the sampling depth must be sealed to prevent 

contamination of samples and the groundwater.

(1) The owner or operator of the CCR unit must document and include in the 

operating record the design, installation, development, and decommissioning of any monitoring 

wells, piezometers and other measurement, sampling, and analytical devices. The qualified 

professional engineer must be given access to this documentation when completing the 

groundwater monitoring system certification required under paragraph (f) of this section.

(2) The monitoring wells, piezometers, and other measurement, sampling, and 

analytical devices must be operated and maintained so that they perform to the design 

specifications throughout the life of the monitoring program.

(f) The owner or operator must obtain a certification from a qualified professional 

engineer stating that the groundwater monitoring system has been designed and constructed to 

meet the requirements of this section. If the groundwater monitoring system includes the 

minimum number of monitoring wells specified in paragraph (c)(1) of this section, the 

certification must document the basis supporting this determination.

(g) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(h), the notification requirements specified in § 257.106(h), 

and the internet requirements specified in § 257.107(h).

§ 257.92 [Reserved]

§ 257.93 Groundwater sampling and analysis requirements.
Document submitted to conclude E.O.12866 Review

677

(a) The groundwater monitoring program must include consistent sampling and 

analysis procedures that are designed to ensure monitoring results that provide an accurate 

representation of groundwater quality at the background and downgradient wells required by § 

257.91. The owner or operator of the CCR unit must develop a sampling and analysis program 

that includes procedures and techniques for:

(1) Sample collection;

(2) Sample preservation and shipment;

(3) Analytical procedures;

(4) Chain of custody control; and

(5) Quality assurance and quality control.

(b) The groundwater monitoring program must include sampling and analytical 

methods that are appropriate for groundwater sampling and that accurately measure hazardous 

constituents and other monitoring parameters in groundwater samples. For purposes of §§ 

257.90 through 257.98, the term constituent refers to both hazardous constituents and other 

monitoring parameters listed in either Appendix III or IV of this part. 

(c) Groundwater elevations must be measured in each well immediately prior to 

purging, each time groundwater is sampled. The owner or operator of the CCR unit must 

determine the rate and direction of groundwater flow each time groundwater is sampled. 

Groundwater elevations in wells which monitor the same CCR management area must be 

measured within a period of time short enough to avoid temporal variations in groundwater flow 

which could preclude accurate determination of groundwater flow rate and direction.

(d) The owner or operator of the CCR unit must establish background groundwater 

quality in a hydraulically upgradient or background well(s) for each of the constituents required 
Document submitted to conclude E.O.12866 Review

678

in the particular groundwater monitoring program that applies to the CCR unit as determined 

under § 257.94(a) or § 257.95(a). Background groundwater quality may be established at wells 

that are not located hydraulically upgradient from the CCR unit if it meets the requirements of § 

257.91(a)(1).

(e) The number of samples collected when conducting detection monitoring and 

assessment monitoring (for both downgradient and background wells) must be consistent with 

the statistical procedures chosen under paragraph (f) of this section and the performance 

standards under paragraph (g) of this section. The sampling procedures shall be those specified 

under § 257.94(b) through (d) for detection monitoring, § 257.95(b) through (d) for assessment 

monitoring, and § 257.96(b) for corrective action.

(f) The owner or operator of the CCR unit must select one of the statistical methods 

specified in paragraphs (f)(1) through (f)(5) of this section to be used in evaluating groundwater 

monitoring data for each specified constituent. The statistical test chosen shall be conducted 

separately for each constituent in each monitoring well.

(1) A parametric analysis of variance followed by multiple comparison procedures to 

identify statistically significant evidence of contamination. The method must include estimation 

and testing of the contrasts between each compliance well's mean and the background mean 

levels for each constituent.

(2) An analysis of variance based on ranks followed by multiple comparison 

procedures to identify statistically significant evidence of contamination. The method must 

include estimation and testing of the contrasts between each compliance well's median and the 

background median levels for each constituent.
Document submitted to conclude E.O.12866 Review

679

(3) A tolerance or prediction interval procedure, in which an interval for each 

constituent is established from the distribution of the background data and the level of each 

constituent in each compliance well is compared to the upper tolerance or prediction limit.

(4) A control chart approach that gives control limits for each constituent.

(5) Another statistical test method that meets the performance standards of paragraph 

(g) of this section.

(6) The owner or operator of the CCR unit must obtain a certification from a qualified 

professional engineer stating that the selected statistical method is appropriate for evaluating the 

groundwater monitoring data for the CCR management area. The certification must include a 

narrative description of the statistical method selected to evaluate the groundwater monitoring 

data.

(g) Any statistical method chosen under paragraph (f) of this section shall comply 

with the following performance standards, as appropriate, based on the statistical test method 

used:

(1) The statistical method used to evaluate groundwater monitoring data shall be 

appropriate for the distribution of constituents. Normal distributions of data values shall use 

parametric methods. Non-normal distributions shall use non-parametric methods. If the 

distribution of the constituents is shown by the owner or operator of the CCR unit to be 

inappropriate for a normal theory test, then the data must be transformed or a distribution-free 

(non-parametric) theory test must be used. If the distributions for the constituents differ, more 

than one statistical method may be needed.

(2) If an individual well comparison procedure is used to compare an individual 

compliance well constituent concentration with background constituent concentrations or a 
Document submitted to conclude E.O.12866 Review

680

groundwater protection standard, the test shall be done at a Type I error level no less than 0.01 

for each testing period. If a multiple comparison procedure is used, the Type I experiment wise 

error rate for each testing period shall be no less than 0.05; however, the Type I error of no less 

than 0.01 for individual well comparisons must be maintained. This performance standard does 

not apply to tolerance intervals, prediction intervals, or control charts.

(3) If a control chart approach is used to evaluate groundwater monitoring data, the 

specific type of control chart and its associated parameter values shall be such that this approach 

is at least as effective as any other approach in this section for evaluating groundwater data. The 

parameter values shall be determined after considering the number of samples in the background 

data base, the data distribution, and the range of the concentration values for each constituent of 

concern.

(4) If a tolerance interval or a predictional interval is used to evaluate groundwater 

monitoring data, the levels of confidence and, for tolerance intervals, the percentage of the 

population that the interval must contain, shall be such that this approach is at least as effective 

as any other approach in this section for evaluating groundwater data. These parameters shall be 

determined after considering the number of samples in the background data base, the data 

distribution, and the range of the concentration values for each constituent of concern.

(5) The statistical method must account for data below the limit of detection with one 

or more statistical procedures that shall at least as effective as any other approach in this section 

for evaluating groundwater data. Any practical quantitation limit that is used in the statistical 

method shall be the lowest concentration level that can be reliably achieved within specified 

limits of precision and accuracy during routine laboratory operating conditions that are available 

to the facility.
Document submitted to conclude E.O.12866 Review

681

(6) If necessary, the statistical method must include procedures to control or correct 

for seasonal and spatial variability as well as temporal correlation in the data.

(h) The owner or operator of the CCR unit must determine whether or not there is a 

statistically significant increase over background values for each constituent required in the 

particular groundwater monitoring program that applies to the CCR unit, as determined under § 

257.94(a) or § 257.95(a).

(1) In determining whether a statistically significant increase has occurred, the owner 

or operator must compare the groundwater quality of each constituent at each monitoring well 

designated pursuant to § 257.91(a)(2) or (d)(1) to the background value of that constituent, 

according to the statistical procedures and performance standards specified under paragraphs (f) 

and (g) of this section.

(2) Within 90 days after completing sampling and analysis, the owner or operator 

must determine whether there has been a statistically significant increase over background for 

any constituent at each monitoring well.

(i) The owner or operator must measure “total recoverable metals”concentrations in 

measuring groundwater quality. Measurement of total recoverable metals captures both the 

particulate fraction and dissolved fraction of metals in natural waters. Groundwater samples 

shall not be field-filtered prior to analysis.

(j) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(h), the notification requirements specified in § 257.106(h), 

and the internet requirements specified in § 257.107(h).

§ 257.94 Detection monitoring program.
Document submitted to conclude E.O.12866 Review

682

(a) The owner or operator of a CCR unit must conduct detection monitoring at all 

groundwater monitoring wells consistent with this section. At a minimum, a detection 

monitoring program must include groundwater monitoring for all constituents listed in Appendix 

III to this part.

(b) Except as provided in paragraph (d) of this section, the monitoring frequency for 

the constituents listed in Appendix III to this part shall be at least semiannual during the active 

life of the CCR unit and the post-closure period. For existing CCR landfills and existing CCR 

surface impoundments, a minimum of eight independent samples from each background and 

downgradient well must be collected and analyzed for the constituents listed in Appendix III and 

Appendix IV to this part no later than [INSERT DATE 30 MONTHS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER]. For new CCR landfills, new CCR surface 

impoundments, and all lateral expansions of CCR units, a minimum of eight independent 

samples for each background well must be collected and analyzed for the constituents listed in 

Appendix III and Appendix IV to this part during the first six months of sampling. 

(c) The number of samples collected and analyzed for each background well and 

downgradient well during subsequent semiannual sampling events must be consistent with § 

257.93(e), and must account for any unique characteristics of the site, but must be at least one 

sample from each background and downgradient well. 

(d) The owner or operator of a CCR unit may demonstrate the need for an alternative 

monitoring frequency for repeated sampling and analysis for constituents listed in Appendix III 

to this part during the active life and the post-closure care period based on the availability of 

groundwater. If there is not adequate groundwater flow to sample wells semiannually, the 

alternative frequency shall be no less than annual. The need to vary monitoring frequency must 
Document submitted to conclude E.O.12866 Review

683

be evaluated on a site-specific basis. The demonstration must be supported by, at a minimum, 

the information specified in paragraphs (d)(1) and (d)(2) of this section.

(1) Information documenting that the need for less frequent sampling. The 

alternative frequency must be based on consideration of the following factors:

(i) Lithology of the aquifer and unsaturated zone;

(ii) Hydraulic conductivity of the aquifer and unsaturated zone; and

(iii) Groundwater flow rates.

(2) Information documenting that the alternative frequency will be no less effective in 

ensuring that any leakage from the CCR unit will be discovered within a timeframe that will not 

materially delay establishment of an assessment monitoring program.

(3) The owner or operator must obtain a certification from a qualified professional 

engineer stating that the demonstration for an alternative groundwater sampling and analysis 

frequency meets the requirements of this section. The owner or operator must include the 

demonstration providing the basis for the alternative monitoring frequency and the certification 

by a qualified professional engineer in the annual groundwater monitoring and corrective action 

report required by § 257.90(e). 

(e) If the owner or operator of the CCR unit determines, pursuant to § 257.93(h) that 

there is a statistically significant increase over background levels for one or more of the 

constituents listed in Appendix III to this part at any monitoring well at the waste boundary 

specified under § 257.91(a)(2), the owner or operator must:

(1) Except as provided for in paragraph (e)(2) of this section, within 90 days of 

detecting a statistically significant increase over background levels for any constituent, establish 

an assessment monitoring program meeting the requirements of § 257.95.
Document submitted to conclude E.O.12866 Review

684

(2) The owner or operator may demonstrate that a source other than the CCR unit 

caused the statistically significant increase over background levels for a constituent or that the 

statistically significant increase resulted from error in sampling, analysis, statistical evaluation, 

or natural variation in groundwater quality. The owner or operator must complete the written 

demonstration within 90 days of detecting a statistically significant increase over background 

levels to include obtaining a certification from a qualified professional engineer verifying the 

accuracy of the information in the report. If a successful demonstration is completed within the 

90-day period, the owner or operator of the CCR unit may continue with a detection monitoring 

program under this section. If a successful demonstration is not completed within the 90-day 

period, the owner or operator of the CCR unit must initiate an assessment monitoring program as 

required under § 257.95. The owner or operator must also include the demonstration in the 

annual groundwater monitoring and corrective action report required by § 257.90(e), in addition 

to the certification by a qualified professional engineer.

(3) The owner or operator of a CCR unit must prepare a notification stating that an 

assessment monitoring program has been established. The owner or operator has completed the 

notification when the notification is placed in the facility’s operating record as required by § 

257.105(h)(5).

(f) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(h), the notification requirements specified in § 257.106(h), 

and the internet requirements specified in § 257.107(h).

§ 257.95 Assessment monitoring program.
Document submitted to conclude E.O.12866 Review

685

(a) Assessment monitoring is required whenever a statistically significant increase 

over background levels has been detected for one or more of the constituents listed in Appendix 

III to this part.

(b) Within 90 days of triggering an assessment monitoring program, and annually 

thereafter, the owner or operator of the CCR unit must sample and analyze the groundwater for 

all constituents listed in Appendix IV to this part. The number of samples collected and 

analyzed for each well during each sampling event must be consistent with § 257.93(e), and must 

account for any unique characteristics of the site, but must be at least one sample from each well.

(c) The owner or operator of a CCR unit may demonstrate the need for an alternative 

monitoring frequency for repeated sampling and analysis for constituents listed in Appendix IV 

to this part during the active life and the post-closure care period based on the availability of 

groundwater. If there is not adequate groundwater flow to sample wells semiannually, the 

alternative frequency shall be no less than annual. The need to vary monitoring frequency must 

be evaluated on a site-specific basis. The demonstration must be supported by, at a minimum, 

the information specified in paragraphs (c)(1) and (c)(2) of this section.

(1) Information documenting that the need for less frequent sampling. The 

alternative frequency must be based on consideration of the following factors:

(i) Lithology of the aquifer and unsaturated zone;

(ii) Hydraulic conductivity of the aquifer and unsaturated zone; and

(iii) Groundwater flow rates.

(2) Information documenting that the alternative frequency will be no less effective in 

ensuring that any leakage from the CCR unit will be discovered within a timeframe that will not 

materially delay the initiation of any necessary remediation measures.
Document submitted to conclude E.O.12866 Review

686

(3) The owner or operator must obtain a certification from a qualified professional 

engineer stating that the demonstration for an alternative groundwater sampling and analysis 

frequency meets the requirements of this section. The owner or operator must include the 

demonstration providing the basis for the alternative monitoring frequency and the certification 

by a qualified professional engineer in the annual groundwater monitoring and corrective action 

report required by § 257.90(e).

(d) After obtaining the results from the initial and subsequent sampling events 

required in paragraph (b) of this section, the owner or operator must:

(1) Within 90 days of obtaining the results, and on at least a semiannual basis 

thereafter, resample all wells that were installed pursuant to the requirements of § 257.91, 

conduct analyses for all parameters in Appendix III to this part and for those constituents in 

Appendix IV to this part that are detected in response to paragraph (b) of this section, and record 

their concentrations in the facility operating record. The number of samples collected and 

analyzed for each background well and downgradient well during subsequent semiannual 

sampling events must be consistent with § 257.93(e), and must account for any unique 

characteristics of the site, but must be at least one sample from each background and 

downgradient well;

(2) Establish groundwater protection standards for all constituents detected pursuant 

to paragraph (b) or (d) of this section. The groundwater protection standards must be established 

in accordance with paragraph (h) of this section; and

(3) Include the recorded concentrations required by paragraph (d)(1) of this section, 

identify the background concentrations established under § 257.94(b), and identify the 
Document submitted to conclude E.O.12866 Review

687

groundwater protection standards established under paragraph (d)(2) of this section in the annual 

groundwater monitoring and corrective action report required by § 257.90(e).

(e) If the concentrations of all constituents listed in Appendix III and Appendix IV to 

this part are shown to be at or below background values, using the statistical procedures in § 

257.93(g), for two consecutive sampling events, the owner or operator may return to detection 

monitoring of the CCR unit. The owner or operator must prepare a notification stating that 

detection monitoring is resuming for the CCR unit. The owner or operator has completed the 

notification when the notification is placed in the facility’s operating record as required by § 

257.105(h)(7).

(f) If the concentrations of any constituent in Appendix III and Appendix IV to this 

part are above background values, but all concentrations are below the groundwater protection 

standard established under paragraph (h) of this section, using the statistical procedures in § 

257.93(g), the owner or operator must continue assessment monitoring in accordance with this 

section.

(g) If one or more constituents in Appendix IV to this part are detected at statistically 

significant levels above the groundwater protection standard established under paragraph (h) of 

this section in any sampling event, the owner or operator must prepare a notification identifying 

the constituents in Appendix IV to this part that have exceeded the groundwater protection 

standard. The owner or operator has completed the notification when the notification is placed in 

the facility’s operating record as required by § 257.105(h)(8). The owner or operator of the CCR 

unit also must:

(1) Characterize the nature and extent of the release and any relevant site conditions 

that may affect the remedy ultimately selected. The characterization must be sufficient to 
Document submitted to conclude E.O.12866 Review

688

support a complete and accurate assessment of the corrective measures necessary to effectively 

clean up all releases from the CCR unit pursuant to § 257.96. Characterization of the release 

includes the following minimum measures: 

(i) Install additional monitoring wells necessary to define the contaminant plume(s); 

(ii) Collect data on the nature and estimated quantity of material released including 

specific information on the constituents listed in Appendix IV of this part and the levels at which 

they are present in the material released; 

(iii) Install at least one additional monitoring well at the facility boundary in the 

direction of contaminant migration and sample this well in accordance with paragraph (d)(1) of 

this section; and

(iv) Sample all wells in accordance with paragraph (d)(1) of this section to 

characterize the nature and extent of the release.

(2) Notify all persons who own the land or reside on the land that directly overlies 

any part of the plume of contamination if contaminants have migrated off-site if indicated by 

sampling of wells in accordance with paragraph (g)(1) of this section. The owner or operator has 

completed the notifications when they are placed in the facility’s operating record as required by 

§ 257.105(h)(8).

(3) Within 90 days of finding that any of the constituents listed in Appendix IV to 

this part have been detected at a statistically significant level exceeding the groundwater 

protection standards the owner or operator must either:

(i) Initiate an assessment of corrective measures as required by § 257.96; or

(ii) Demonstrate that a source other than the CCR unit caused the contamination, or 

that the statistically significant increase resulted from error in sampling, analysis, statistical 
Document submitted to conclude E.O.12866 Review

689

evaluation, or natural variation in groundwater quality. Any such demonstration must be 

supported by a report that includes the factual or evidentiary basis for any conclusions and must 

be certified to be accurate by a qualified professional engineer. If a successful demonstration is 

made, the owner or operator must continue monitoring in accordance with the assessment 

monitoring program pursuant to this section, and may return to detection monitoring if the 

constituents in Appendix III and Appendix IV to this part are at or below background as 

specified in paragraph (e) of this section. The owner or operator must also include the 

demonstration in the annual groundwater monitoring and corrective action report required by § 

257.90(e), in addition to the certification by a qualified professional engineer.

(4) If a successful demonstration has not been made at the end of the 90 day period 

provided by paragraph (g)(3)(ii) of this section, the owner or operator of the CCR unit must 

initiate the assessment of corrective measures requirements under § 257.96.

(5) If an assessment of corrective measures is required under § 257.96 by either 

paragraph (g)(3)(i) or (g)(4) of this section, and if the CCR unit is an existing unlined CCR 

surface impoundment as determined by § 257.71(a), then the CCR unit is subject to the closure 

requirements under § 257.101(a). In addition, the owner or operator must prepare a notification 

stating that an assessment of corrective measures has been initiated.

(h) The owner or operator of the CCR unit must establish a groundwater protection 

standard for each constituent in Appendix IV to this part detected in the groundwater. The 

groundwater protection standard shall be:

(1) For constituents for which a maximum contaminant level (MCL) has been 

established under §§141.62 and 141.66 of this title, the MCL for that constituent;
Document submitted to conclude E.O.12866 Review

690

(2) For constituents for which an MCL has not been established, the background 

concentration for the constituent established from wells in accordance with § 257.91; or

(3) For constituents for which the background level is higher than the MCL identified 

under paragraph (h)(1) of this section, the background concentration.

(i) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(h), the notification requirements specified in § 257.106(h), 

and the internet requirements specified in § 257.107(h).

§ 257.96 Assessment of corrective measures.

(a) Within 90 days of finding that any constituent listed in Appendix IV to this part 

has been detected at a statistically significant level exceeding the groundwater protection 

standard defined under § 257.95(h), or immediately upon detection of a release from a CCR unit, 

the owner or operator must initiate an assessment of corrective measures to prevent further 

releases, to remediate any releases and to restore affected area to original conditions. The 

assessment of corrective measures must be completed within 90 days, unless the owner or 

operator demonstrates the need for additional time to complete the assessment of corrective 

measures due to site-specific conditions or circumstances. The owner or operator must obtain a 

certification from a qualified professional engineer attesting that the demonstration is accurate. 

The 90-day deadline to complete the assessment of corrective measures may be extended for no 

longer than 60 days. The owner or operator must also include the demonstration in the annual 

groundwater monitoring and corrective action report required by § 257.90(e), in addition to the 

certification by a qualified professional engineer.

(b) The owner or operator of the CCR unit must continue to monitor groundwater in 

accordance with the assessment monitoring program as specified in § 257.95.
Document submitted to conclude E.O.12866 Review

691

(c) The assessment under paragraph (a) of this section must include an analysis of the 

effectiveness of potential corrective measures in meeting all of the requirements and objectives 

of the remedy as described under § 257.97 addressing at least the following:

(1) The performance, reliability, ease of implementation, and potential impacts of 

appropriate potential remedies, including safety impacts, cross-media impacts, and control of 

exposure to any residual contamination;

(2) The time required to begin and complete the remedy;

(3) The institutional requirements, such as state or local permit requirements or other 

environmental or public health requirements that may substantially affect implementation of the 

remedy(s).

(d) The owner or operator must place the completed assessment of corrective 

measures in the facility’s operating record. The assessment has been completed when it is placed 

in the facility’s operating record as required by § 257.105(h)(7).

(e) The owner or operator must discuss the results of the corrective measures 

assessment at least 30 days prior to the selection of remedy, in a public meeting with interested 

and affected parties.

(f) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(h), the notification requirements specified in § 257.106(h), 

and the internet requirements specified in § 257.107(h).

§ 257.97 Selection of remedy.

(a) Based on the results of the corrective measures assessment conducted under § 

257.96, the owner or operator must, as soon as feasible, select a remedy that, at a minimum, 

meets the standards listed in paragraph (b) of this section. This requirement applies to, not in 
Document submitted to conclude E.O.12866 Review

692

place of, any applicable standards under the Occupational Safety and Health Act. The owner or 

operator must prepare a semiannual report describing the progress in selecting and designing the 

remedy. Upon selection of a remedy, the owner or operator must prepare a final report 

describing the selected remedy and how it meets the standards specified in paragraph (b) of this 

section. The owner or operator must obtain a certification from a qualified professional engineer 

that the remedy selected meets the requirements of this section. The report has been completed 

when it is placed in the operating record as required by § 257.105(h)(12). 

(b) Remedies must:

(1) Be protective of human health and the environment;

(2) Attain the groundwater protection standard as specified pursuant to § 257.95(h);

(3) Control the source(s) of releases so as to reduce or eliminate, to the maximum 

extent feasible, further releases of constituents in Appendix IV to this part into the environment;

(4) Remove from the environment as much of the contaminated material that was 

released from the CCR unit as is feasible, taking into account factors such as avoiding 

inappropriate disturbance of sensitive ecosystems;

(5) Comply with standards for management of wastes as specified in § 257.98(d).

(c) In selecting a remedy that meets the standards of paragraph (b) of this section, the 

owner or operator of the CCR unit shall consider the following evaluation factors:

(1) The long- and short-term effectiveness and protectiveness of the potential 

remedy(s), along with the degree of certainty that the remedy will prove successful based on 

consideration of the following:

(i) Magnitude of reduction of existing risks;
Document submitted to conclude E.O.12866 Review

693

(ii) Magnitude of residual risks in terms of likelihood of further releases due to CCR 

remaining following implementation of a remedy;

(iii) The type and degree of long-term management required, including monitoring, 

operation, and maintenance;

(iv) Short-term risks that might be posed to the community or the environment during 

implementation of such a remedy, including potential threats to human health and the 

environment associated with excavation, transportation, and re-disposal of contaminant;

(v) Time until full protection is achieved;

(vi) Potential for exposure of humans and environmental receptors to remaining 

wastes, considering the potential threat to human health and the environment associated with 

excavation, transportation, re-disposal, or containment;

(vii) Long-term reliability of the engineering and institutional controls; and

(viii) Potential need for replacement of the remedy.

(2) The effectiveness of the remedy in controlling the source to reduce further 

releases based on consideration of the following factors:

(i) The extent to which containment practices will reduce further releases; and

(ii) The extent to which treatment technologies may be used.

(3) The ease or difficulty of implementing a potential remedy(s) based on 

consideration of the following types of factors:

(i) Degree of difficulty associated with constructing the technology;

(ii) Expected operational reliability of the technologies;

(iii) Need to coordinate with and obtain necessary approvals and permits from other 

agencies;
Document submitted to conclude E.O.12866 Review

694

(iv) Availability of necessary equipment and specialists; and

(v) Available capacity and location of needed treatment, storage, and disposal 

services.

(4) The degree to which community concerns are addressed by a potential remedy(s).

(d) The owner or operator must specify as part of the selected remedy a schedule(s) 

for implementing and completing remedial activities. Such a schedule must require the 

completion of remedial activities within a reasonable period of time taking into consideration the 

factors set forth in paragraphs (d)(1) through (d)(6) of this section. The owner or operator of the 

CCR unit must consider the following factors in determining the schedule of remedial activities:

(1) Extent and nature of contamination, as determined by the characterization 

required under § 257.95(g);

(2) Reasonable probabilities of remedial technologies in achieving compliance with 

the groundwater protection standards established under § 257.95(h) and other objectives of the 

remedy;

(3) Availability of treatment or disposal capacity for CCR managed during 

implementation of the remedy;

(4) Potential risks to human health and the environment from exposure to 

contamination prior to completion of the remedy;

(5) Resource value of the aquifer including:

(i) Current and future uses;

(ii) Proximity and withdrawal rate of users;

(iii) Groundwater quantity and quality;
Document submitted to conclude E.O.12866 Review

695

(iv) The potential damage to wildlife, crops, vegetation, and physical structures 

caused by exposure to CCR constituents;

(v) The hydrogeologic characteristic of the facility and surrounding land; and

(vi) The availability of alternative water supplies; and

(6) Other relevant factors.

(e) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(h), the notification requirements specified in § 257.106(h), 

and the internet requirements specified in § 257.107(h).

§ 257.98 Implementation of the corrective action program.

(a) Within 90 days of selecting a remedy under § 257.97, the owner or operator must 

initiate remedial activities. Based on the schedule established under § 257.97(d) for 

implementation and completion of remedial activities the owner or operator must:

(1) Establish and implement a corrective action groundwater monitoring program 

that:

(i) At a minimum, meets the requirements of an assessment monitoring program 

under § 257.95;

(ii) Documents the effectiveness of the corrective action remedy; and

(iii) Demonstrates compliance with the groundwater protection standard pursuant to 

paragraph (c) of this section.

(2) Implement the corrective action remedy selected under § 257.97; and

(3) Take any interim measures necessary to reduce the contaminants leaching from 

the CCR unit, and/or potential exposures to human or ecological receptors. Interim measures 

must, to the greatest extent feasible, be consistent with the objectives of and contribute to the 
Document submitted to conclude E.O.12866 Review

696

performance of any remedy that may be required pursuant to § 257.97. The following factors 

must be considered by an owner or operator in determining whether interim measures are 

necessary:

(i) Time required to develop and implement a final remedy;

(ii) Actual or potential exposure of nearby populations or environmental receptors to 

any of the constituents listed in Appendix IV of this part;

(iii) Actual or potential contamination of drinking water supplies or sensitive 

ecosystems;

(iv) Further degradation of the groundwater that may occur if remedial action is not 

initiated expeditiously;

(v) Weather conditions that may cause any of the constituents listed in Appendix IV 

to this part to migrate or be released;

(vi) Potential for exposure to any of the constituents listed in Appendix IV to this part 

as a result of an accident or failure of a container or handling system; and

(vii) Other situations that may pose threats to human health and the environment.

(b) If an owner or operator of the CCR unit, determines, at any time, that compliance 

with the requirements of § 257.97(b) is not being achieved through the remedy selected, the 

owner or operator must implement other methods or techniques that could feasibly achieve 

compliance with the requirements.

(c) Remedies selected pursuant to § 257.97 shall be considered complete when:

(1) The owner or operator of the CCR unit demonstrates compliance with the 

groundwater protection standards established under § 257.95(h) has been achieved at all points 
Document submitted to conclude E.O.12866 Review

697

within the plume of contamination that lie beyond the groundwater monitoring well system 

established under § 257.91.

(2) Compliance with the groundwater protection standards established under § 257.95 

(h) has been achieved by demonstrating that concentrations of constituents listed in Appendix IV 

to this part have not exceeded the groundwater protection standard(s) for a period of three 

consecutive years using the statistical procedures and performance standards in § 257.93(f) and 

(g). 

(3) All actions required to complete the remedy have been satisfied.

(d) All CCR that are managed pursuant to a remedy required under § 257.97, or an 

interim measure required under paragraph (a)(3) of this section, shall be managed in a manner 

that complies with all applicable RCRA requirements.

(e) Upon completion of the remedy, the owner or operator must prepare a notification 

stating that the remedy has been completed. The owner or operator must obtain a certification 

from a qualified professional engineer attesting that the remedy has been completed in 

compliance with the requirements of paragraph (c) of this section. The report has been 

completed when it is placed in the operating record as required by § 257.105(h)(13).

(f) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(h), the notification requirements specified in § 257.106(h), 

and the internet requirements specified in § 257.107(h).

Closure and Post-Closure Care

§ 257.100 Inactive CCR surface impoundments.
Document submitted to conclude E.O.12866 Review

698

(a) Except as provided by paragraph (b) of this section, inactive CCR surface 

impoundments are subject to all of the requirements of this subpart applicable to existing CCR 

surface impoundments.

(b) An owner or operator of an inactive CCR surface impoundment that completes 

closure of such CCR unit, and meets all of the requirements of either paragraphs (b)(1) through 

(b)(4) of this section or paragraph (b)(5) of this section no later than [INSERT DATE 36 

MONTHS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER], is exempt 

from all other requirements of this subpart.

(1) Closure by leaving CCR in place. If the owner or operator of the inactive CCR 

surface impoundment elects to close the CCR surface impoundment by leaving CCR in place, 

the owner or operator must ensure that, at a minimum, the CCR unit is closed in a manner that 

will:

(i) Control, minimize or eliminate, to the maximum extent feasible, postclosure infiltration of liquids into the waste and releases of CCR, leachate, or contaminated runoff to the ground or surface waters or to the atmosphere;

(ii) Preclude the probability of future impoundment of water, sediment, or 

slurry;

(iii) Include measures that provide for major slope stability to prevent the 

sloughing or movement of the final cover system during closure and throughout the post-closure 

care period; and

(iv) Minimize the need for further maintenance of the CCR unit.
Document submitted to conclude E.O.12866 Review

699

(2) The owner or operator of the inactive CCR surface impoundment must meet the 

requirements of paragraphs (b)(2)(i) and (b)(2)(ii) of this section prior to installing the final 

cover system required under paragraph (b)(3) of this section.

(i) Free liquids must be eliminated by removing liquid wastes or solidifying 

the remaining wastes and waste residues.

(ii) Remaining wastes must be stabilized sufficient to support the final cover system.

(3) The owner or operator must install a final cover system that is designed to 

minimize infiltration and erosion, and at a minimum, meets the requirements of paragraph 

(b)(3)(i) of this section, or the requirements of an alternative final cover system specified in 

paragraph (b)(3)(ii) of this section.

(i) The final cover system must be designed and constructed to meet the criteria 

specified in paragraphs (b)(3)(i)(A) through (b)(3)(i)(D) of this section.

(A) The permeability of the final cover system must be less than or equal to the 

permeability of any bottom liner system or natural subsoils present, or a permeability no greater 

than 1x10-5centimeters/second, whichever is less.

(B) The infiltration of liquids through the CCR unit must be minimized by the use of 

an infiltration layer that contains a minimum of 18 inches of earthen material.

(C) The erosion of the final cover system must be minimized by the use of an erosion 

layer that contains a minimum of 6 inches of earthen material that is capable of sustaining native 

plant growth.

(D) The disruption of the integrity of the final cover system must be minimized 

through a design that accommodates settling and subsidence.
Document submitted to conclude E.O.12866 Review

700

(ii) The owner or operator may select an alternative final cover system design, 

provided the alternative final cover system is designed and constructed to meet the criteria in 

paragraphs (b)(3)(ii)(A) through (b)(3)(ii)(C) of this section.

(A) The design of the final cover system must include an infiltration layer that 

achieves an equivalent reduction in infiltration as the infiltration layer specified in paragraphs 

(b)(3)(i)(A) and (b)(3)(i)(B) of this section.

(B) The design of the final cover system must include an erosion layer that provides 

equivalent protection from wind or water erosion as the erosion layer specified in paragraph 

(b)(3)(i)(C) of this section.

(C) The disruption of the integrity of the final cover system must be minimized 

through a design that accommodates settling and subsidence.

(4) The owner or operator of the CCR surface impoundment must obtain a written 

certification from a qualified professional engineer stating that the design of the final cover 

system meets either the requirements of paragraphs (b)(3)(i) or (b)(3)(ii) of this section.

(5) Closure through removal of CCR. The owner or operator may 

alternatively elect to close an inactive CCR surface impoundment by removing and 

decontaminating all areas affected by releases from the CCR surface impoundment. CCR 

removal and decontamination of the CCR surface impoundment are complete when all CCR in 

the inactive CCR surface impoundment is removed, including the bottom liner of the CCR unit.

(6) The owner or operator of the CCR surface impoundment must obtain a 

written certification from a qualified professional engineer that closure of the CCR surface 

impoundment under either paragraphs (b)(1) through (b)(4) or (b)(5) of this section is technically 

feasible within the timeframe in paragraph (b) of this section.
Document submitted to conclude E.O.12866 Review

701

(7) If the owner or operator of the CCR surface impoundment fails to 

complete closure of the inactive CCR surface impoundment within the timeframe in paragraph 

(b) of this section, the CCR unit must comply with all of the requirements applicable to existing 

CCR surface impoundments under this subpart.

(c) Required notices and progress reports. An owner or operator of an 

inactive CCR surface impoundment that closes in accordance with paragraph (b) of this section 

must complete the notices and progress reports specified in paragraphs (c)(1) through (c)(3) of 

this section.

(1) No later than [INSERT DATE 8 MONTHS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER], the owner or operator must prepare and 

place in the facility’s operating record a notification of intent to initiate closure of the CCR 

surface impoundment. The notification must state that the CCR surface impoundment is an 

inactive CCR surface impoundment closing under the requirements of paragraph (b) of this 

section. The notification must also include a narrative description of how the CCR surface 

impoundment will be closed, a schedule for completing closure activities, and the required 

certifications under paragraphs (b)(4) and (b)(6) of this section, if applicable.

(2) The owner or operator must prepare periodic progress reports 

summarizing the progress of closure implementation, including a description of the actions 

completed to date, any problems encountered and a description of the actions taken to resolve the 

problems, and projected closure activities for the upcoming year. The annual progress reports 

must be completed according to the following schedule:
Document submitted to conclude E.O.12866 Review

702

(i) The first annual progress report must be prepared no later than 13 months 

after completing the notification of intent to initiate closure required by paragraph (c)(1) of this 

section.

(ii) The second annual progress report must be prepared no later than 12 

months after completing the first progress report required by paragraph (c)(2)(i) of this section.

(iii) The owner or operator has completed the progress reports specified in paragraph 

(c)(2) of this section when the reports are placed in the facility’s operating record as required by 

§ 257.105(i)(2).

(3) The owner or operator must prepare and place in the facility’s operating 

record a notification of completion of closure of the CCR surface impoundment. The 

notification must be submitted within 60 days of completing closure of the CCR surface 

impoundment and must include a written certification from a qualified professional engineer 

stating that the CCR surface impoundment was closed in accordance with the requirements of 

either paragraph (b)(1) through (b)(4) or (b)(5) of this section.

(d) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(i), the notification requirements specified in § 257.106(i), 

and the internet requirements specified in § 257.107(i).

§ 257.101Closure of CCR landfills and CCR surface impoundments.

(a) The owner or operator of an existing unlined CCR surface impoundment, 

as determined under § 257.71(a), is subject to the requirements of paragraph (a)(1) of this 

section.

(1) Except as provided by paragraph (a)(3) of this section, if at any time after 

[INSERT DATE 6 MONTHS AFTER DATE OF PUBLICATION IN THE FEDERAL 
Document submitted to conclude E.O.12866 Review

703

REGISTER] an owner or operator of an existing unlined CCR surface impoundment determines 

in any sampling event that the concentrations of one or more constituents listed in Appendix IV 

to this part are detected at statistically significant levels above the groundwater protection 

standard established under § 257.95(h) for such CCR unit, within six months of making such 

determination, the owner or operator of the existing unlined CCR surface impoundment must 

cease placing CCR and non-CCR wastestreams into such CCR surface impoundment and close 

the CCR unit in accordance with the requirements of § 257.102.

(2) An owner or operator of an existing unlined CCR surface impoundment that 

closes in accordance with paragraph (a)(1) of this section must include a statement in the 

notification required under § 257.102(g) that the CCR surface impoundment is closing under the 

requirements of paragraph (a)(1) of this section.

(3) The timeframe specified in paragraph (a)(1) of this section does not apply if the 

owner or operator complies with the alternative closure procedures specified in § 257.103.

(b) The owner or operator of an existing CCR surface impoundment is subject to the 

requirements of paragraph (b)(1) of this section.

(1) Except as provided by paragraph (b)(4) of this section, within six months of 

determining that an existing CCR surface impoundment has not demonstrated compliance with 

any location standard specified in §§ 257.60(a), 257.61(a), 257.62(a), 257.63(a), and 257.64(a), 

the owner or operator of the CCR surface impoundment must cease placing CCR and non-CCR 

wastestreams into such CCR unit and close the CCR unit in accordance with the requirements of 

§ 257.102.

(2) Within six months of either failing to complete the initial or any subsequent 

periodic safety factor assessment required by § 257.73(e) by the deadlines specified in § 
Document submitted to conclude E.O.12866 Review

704

257.73(f)(1) through (f)(3) or failing to document that the calculated factors of safety for the 

existing CCR surface impoundment achieve the minimum safety factors specified in § 

257.73(e)(1)(i) through (e)(1)(iv), the owner or operator of the CCR surface impoundment must 

cease placing CCR and non-CCR wastestreams into such CCR unit and close the CCR unit in 

accordance with the requirements of § 257.102.

(3) An owner or operator of an existing CCR surface impoundment that closes in 

accordance with paragraphs (b)(1) or (b)(2) of this section must include a statement in the 

notification required under § 257.102(g) that the CCR surface impoundment is closing under the 

requirements of paragraphs (b)(1) or (b)(2) of this section.

(4) The timeframe specified in paragraph (b)(1) of this section does not apply if the 

owner or operator complies with the alternative closure procedures specified in § 257.103.

(c) The owner or operator of a new CCR surface impoundment is subject to the 

requirements of paragraph (c)(1) of this section.

(1) Within six months of either failing to complete the initial or any subsequent 

periodic safety factor assessment required by § 257.74(e) by the deadlines specified in § 

257.74(f)(1) through (f)(3) or failing to document that the calculated factors of safety for the new 

CCR surface impoundment achieve the minimum safety factors specified in § 257.74(e)(1)(i) 

through (e)(1)(v), the owner or operator of the CCR surface impoundment must cease placing 

CCR and non-CCR wastestreams into such CCR unit and close the CCR unit in accordance with 

the requirements of § 257.102.

(2) An owner or operator of an new CCR surface impoundment that closes in 

accordance with paragraph (c)(1) of this section must include a statement in the notification 
Document submitted to conclude E.O.12866 Review

705

required under § 257.102(g) that the CCR surface impoundment is closing under the 

requirements of paragraph (c)(1) of this section.

(d) The owner or operator of an existing CCR landfill is subject to the requirements 

of paragraph (d)(1) of this section.

(1) Except as provided by paragraph (d)(3) of this section, within six months of 

determining that an existing CCR landfill has not demonstrated compliance with the location 

restriction for unstable areas specified in § 257.64(a), the owner or operator of the CCR unit 

must cease placing CCR and non-CCR wastestreams into such CCR landfill and close the CCR 

unit in accordance with the requirements of § 257.102.

(2) An owner or operator of an existing CCR landfill that closes in accordance with 

paragraph (d)(1) of this section must include a statement in the notification required under § 

257.102(g) that the CCR landfill is closing under the requirements of paragraph (d)(1) of this 

section.

(3) The timeframe specified in paragraph (d)(1) of this section does not apply if the 

owner or operator complies with the alternative closure procedures specified in § 257.103.

§ 257.102Criteria for conducting closure of CCR landfills and CCR surface 

impoundments.

(a) Closure of a CCR landfill, CCR surface impoundment, or any lateral expansion of 

a CCR unit must be completed either by leaving the CCR in place and installing a final cover 

system or through removal of the CCR and decontamination of the CCR unit, as described in this 

section.

(b) Written Closure Plan. (1) Content of the plan. The owner or operator of a CCR 

unit must prepare a written closure plan that describes the steps necessary to close the CCR unit 
Document submitted to conclude E.O.12866 Review

706

at any point during the active life of the CCR unit consistent with recognized and generally 

accepted good engineering practices. The written closure plan must include, at a minimum, the 

information specified in paragraphs (b)(1)(i) through (b)(1)(vi) of this section.

(i) A narrative description of how the CCR unit will be closed in accordance with 

this section.

(ii) If closure of the CCR unit will be accomplished through removal of CCR from 

the CCR unit, a description of the procedures to remove the CCR and decontaminate the CCR 

unit in accordance with paragraph (c) of this section.

(iii) If closure of the CCR unit will be accomplished by leaving CCR in place, a 

description of the final cover system, designed in accordance with paragraph (d) of this section, 

and the methods and procedures to be used to install the final cover. The closure plan must also 

discuss how the final cover system will achieve the performance standards specified in paragraph 

(d) of this section.

(iv) An estimate of the maximum inventory of CCR ever on-site over the active life of 

the CCR unit.

(v) An estimate of the largest area of the CCR unit ever requiring a final cover as 

required by paragraph (d) of this section at any time during the CCR unit’s active life.

(vi) A schedule for completing all activities necessary to satisfy the closure criteria in 

this section, including an estimate of the year in which all closure activities for the CCR unit will 

be completed. The schedule should provide sufficient information to describe the sequential 

steps that will be taken to close the CCR unit, including identification of major milestones such 

as coordinating with and obtaining necessary approvals and permits from other agencies, the 

dewatering and stabilization phases of CCR surface impoundment closure, or installation of the 
Document submitted to conclude E.O.12866 Review

707

final cover system, and the estimated timeframes to complete each step or phase of CCR unit 

closure. When preparing the written closure plan, if the owner or operator of a CCR unit 

estimates that the time required to complete closure will exceed the timeframes specified in 

paragraph (f)(1) of this section, the written closure plan must include the site-specific 

information, factors and considerations that would support any time extension sought under 

paragraph (f)(2) of this section. 

(2) Timeframes for preparing the initial written closure plan. (i) Existing CCR 

landfills and existing CCR surface impoundments. No later than [INSERT DATE 18 

MONTHS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER], the 

owner or operator of the CCR unit must prepare an initial written closure plan consistent with the 

requirements specified in paragraph (b)(1) of this section.

(ii) New CCR landfills and new CCR surface impoundments, and any lateral 

expansion of a CCR unit. No later than the date of the initial receipt of CCR in the CCR unit, the 

owner or operator must prepare an initial written closure plan consistent with the requirements 

specified in paragraph (b)(1) of this section.

(iii) The owner or operator has completed the written closure plan when the plan, 

including the certification required by paragraph (b)(4) of this section, has been placed in the 

facility’s operating record as required by § 257.105(i)(4).

(3) Amendment of a written closure plan. (i) The owner or operator may amend the 

initial or any subsequent written closure plan developed pursuant to paragraph (b)(1) of this 

section at any time.

(ii) The owner or operator must amend the written closure plan whenever:
Document submitted to conclude E.O.12866 Review

708

(A) There is a change in the operation of the CCR unit that would substantially affect 

the written closure plan in effect; or

(B) Before or after closure activities have commenced, unanticipated events 

necessitate a revision of the written closure plan.

(iii) The owner or operator must amend the closure plan at least 60 days prior to a 

planned change in the operation of the facility or CCR unit, or no later than 60 days after an 

unanticipated event requires the need to revise an existing written closure plan. If a written 

closure plan is revised after closure activities have commenced for a CCR unit, the owner or 

operator must amend the current closure plan no later than 30 days following the triggering 

event.

(4) The owner or operator of the CCR unit must obtain a written certification from a 

qualified professional engineer that the initial and any amendment of the written closure plan 

meets the requirements of this section.

(c) Closure by removal of CCR. An owner or operator may elect to close a CCR unit 

by removing and decontaminating all areas affected by releases from the CCR unit. CCR 

removal and decontamination of the CCR unit are complete when constituent concentrations 

throughout the CCR unit and any areas affected by releases from the CCR unit have been 

removed and groundwater monitoring concentrations do not exceed the groundwater protection 

standard established pursuant to § 257.95(h) for constituents listed in Appendix IV to this part.

(d) Closure performance standard when leaving CCR in place. (1) The owner or 

operator of a CCR unit must ensure that, at a minimum, the CCR unit is closed in a manner that 

will:
Document submitted to conclude E.O.12866 Review

709

(i) Control, minimize or eliminate, to the maximum extent feasible, post-closure 

infiltration of liquids into the waste and releases of CCR, leachate, or contaminated run-off to the 

ground or surface waters or to the atmosphere;

(ii) Preclude the probability of future impoundment of water, sediment, or slurry;

(iii) Include measures that provide for major slope stability to prevent the sloughing or

movement of the final cover system during the closure and post-closure care period;

(iv) Minimize the need for further maintenance of the CCR unit; and

(v) Be completed in the shortest amount of time consistent with recognized and 

generally accepted good engineering practices.

(2) Drainage and stabilization of CCR surface impoundments. The owner or operator 

of a CCR surface impoundment or any lateral expansion of a CCR surface impoundment must 

meet the requirements of paragraphs (d)(2)(i) and (d)(2)(ii) of this section prior to installing the 

final cover system required under paragraph (d)(3) of this section.

(i) Free liquids must be eliminated by removing liquid wastes or solidifying the 

remaining wastes and waste residues.

(ii) Remaining wastes must be stabilized sufficient to support the final cover system.

(3) Final cover system. If a CCR unit is closed by leaving CCR in place, the owner 

or operator must install a final cover system that is designed to minimize infiltration and erosion, 

and at a minimum, meets the requirements of paragraph (d)(3)(i) of this section, or the 

requirements of the alternative final cover system specified in paragraph (d)(3)(ii) of this section.

(i) The final cover system must be designed and constructed to meet the criteria in 

paragraphs (d)(3)(i)(A) through (d)(3)(i)(D) of this section. The design of the final cover system 

must be included in the written closure plan required by paragraph (b) of this section.
Document submitted to conclude E.O.12866 Review

710

(A) The permeability of the final cover system must be less than or equal to the 

permeability of any bottom liner system or natural subsoils present, or a permeability no greater 

than 1x10-5cm/sec, whichever is less.

(B) The infiltration of liquids through the closed CCR unit must be minimized by the 

use of an infiltration layer that contains a minimum of 18 inches of earthen material.

(C) The erosion of the final cover system must be minimized by the use of an erosion 

layer that contains a minimum of 6 inches of earthen material that is capable of sustaining native 

plant growth.

(D) The disruption of the integrity of the final cover system must be minimized 

through a design that accommodates settling and subsidence.

(ii) The owner or operator may select an alternative final cover system design, 

provided the alternative final cover system is designed and constructed to meet the criteria in 

paragraphs (f)(3)(ii)(A) through (f)(3)(ii)(D) of this section. The design of the final cover system 

must be included in the written closure plan required by paragraph (b) of this section.

(A) The design of the final cover system must include an infiltration layer that 

achieves an equivalent reduction in infiltration as the infiltration layer specified in paragraphs 

(d)(3)(i)(A) and (d)(3)(i)(B) of this section.

(B) The design of the final cover system must include an erosion layer that provides 

equivalent protection from wind or water erosion as the erosion layer specified in paragraph 

(d)(3)(i)(C) of this section.

(C) The disruption of the integrity of the final cover system must be minimized 

through a design that accommodates settling and subsidence.
Document submitted to conclude E.O.12866 Review

711

(iii) The owner or operator of the CCR unit must obtain a written certification from a 

qualified professional engineer that the design of the final cover system meets the requirements 

of this section.

(e) Initiation of closure activities. Except as provided for in paragraph (e)(4) of this 

section and § 257.103, the owner or operator of a CCR unit must commence closure of the CCR 

unit no later than the applicable timeframes specified in either paragraph (e)(1) or (e)(2) of this 

section.

(1) The owner or operator must commence closure of the CCR unit no later than 30 

days after the date on which the CCR unit either:

(i) Receives the known final receipt of waste, either CCR or any non-CCR 

wastestream; or

(ii) Removes the known final volume of CCR from the CCR unit for the purpose of 

beneficial use of CCR.

(2)(i) Except as provided by paragraph (e)(2)(ii) of this section, the owner or operator 

must commence closure of a CCR unit that has not received CCR or any non-CCR wastestream 

or is no longer removing CCR for the purpose of beneficial use within two years of the last 

receipt of waste or within two years of the last removal of CCR material for the purpose of 

beneficial use.

(ii) Notwithstanding paragraph (e)(2)(i) of this section, the owner or operator of the 

CCR unit may secure an additional two years to initiate closure of the idle unit provided the 

owner or operator provides written documentation that the CCR unit will continue to accept 

wastes or will start removing CCR for the purpose of beneficial use. The documentation must be 

supported by, at a minimum, the information specified in paragraphs (e)(2)(ii)(A) and 
Document submitted to conclude E.O.12866 Review

712

(e)(2)(ii)(B) of this section. The owner or operator may obtain two-year extensions provided the 

owner or operator continues to be able to demonstrate that there is reasonable likelihood that the 

CCR unit will accept wastes in the foreseeable future or will remove CCR from the unit for the 

purpose of beneficial use. The owner or operator must place each completed demonstration, if 

more than one time extension is sought, in the facility’s operating record as required by § 

257.105(i)(5) prior to the end of any two-year period.

(A) Information documenting that the CCR unit has remaining storage or disposal 

capacity or that the CCR unit can have CCR removed for the purpose of beneficial use; and

(B) Information demonstrating that that there is a reasonable likelihood that the CCR 

unit will resume receiving CCR or non-CCR wastestreams in the foreseeable future or that CCR 

can be removed for the purpose of beneficial use. The narrative must include a best estimate as 

to when the CCR unit will resume receiving CCR or non-CCR wastestreams. The situations 

listed in paragraphs (e)(2)(ii)(B)(1) through (e)(2)(ii)(B)(4) of this section are examples of 

situations that would support a determination that the CCR unit will resume receiving CCR or 

non-CCR wastestreams in the foreseeable future.

(1) Normal plant operations include periods during which the CCR unit does not 

receive CCR or non-CCR wastestreams, such as the alternating use of two or more CCR units 

whereby at any point in time one CCR unit is receiving CCR while CCR is being removed from 

a second CCR unit after its dewatering.

(2) The CCR unit is dedicated to a coal-fired boiler unit that is temporarily idled (e.g., 

CCR is not being generated) and there is a reasonable likelihood that the coal-fired boiler will 

resume operations in the future.
Document submitted to conclude E.O.12866 Review

713

(3) The CCR unit is dedicated to an operating coal-fired boiler (i.e., CCR is being 

generated); however, no CCR are being placed in the CCR unit because the CCR are being 

entirely diverted to beneficial uses, but there is a reasonable likelihood that the CCR unit will 

again be used in the foreseeable future.

(4) The CCR unit currently receives only non-CCR wastestreams and those non-CCR 

wastestreams are not generated for an extended period of time, but there is a reasonable 

likelihood that the CCR unit will again receive non-CCR wastestreams in the future.

(iii) In order to obtain additional time extension(s) to initiate closure of a CCR unit 

beyond the two years provided by paragraph (e)(2)(i) of this section, the owner or operator of the 

CCR unit must include with the demonstration required by paragraph (e)(2)(ii) of this section the 

following statement signed by the owner or operator or an authorized representative:

I certify under penalty of law that I have personally examined and am 

familiar with the information submitted in this demonstration and all attached 

documents, and that, based on my inquiry of those individuals immediately 

responsible for obtaining the information, I believe that the submitted information 

is true, accurate, and complete. I am aware that there are significant penalties for 

submitting false information, including the possibility of fine and imprisonment.

(3) For purposes of this subpart, closure of the CCR unit has commenced if the owner 

or operator has ceased placing waste and completes any of the following actions or activities:

(i) Taken any steps necessary to implement the written closure plan required by 

paragraph (b) of this section;

(ii) Submitted a completed application for any required state or agency permit or 

permit modification; or
Document submitted to conclude E.O.12866 Review

714

(iii) Taken any steps necessary to comply with any state or other agency standards that 

are a prerequisite, or are otherwise applicable, to initiating or completing the closure of a CCR 

unit.

(4) The timeframes specified in paragraphs (e)(1) and (e)(2) of this section do not 

apply to any of the following owners or operators:

(i) An owner or operator of an inactive CCR surface impoundment closing the CCR 

unit as required by § 257.100(b);

(ii) An owner or operator of an existing unlined CCR surface impoundment closing 

the CCR unit as required by § 257.101(a); 

(iii) An owner or operator of an existing CCR surface impoundment closing the CCR 

unit as required by § 257.101(b);

(iv) An owner or operator of a new CCR surface impoundment closing the CCR unit 

as required by § 257.101(c); or

(v) An owner or operator of an existing CCR landfill closing the CCR unit as 

required by § 257.101(d).

(f) Completion of closure activities. (1) Except as provided for in paragraph (f)(2) of 

this section, the owner or operator must complete closure of the CCR unit:

(i) For existing and new CCR landfills and any lateral expansion of a CCR landfill, 

within six months of commencing closure activities pursuant to either paragraph (e)(1) or (e)(2) 

of this section.

(ii) For existing and new CCR surface impoundments and any lateral expansion of a 

CCR surface impoundment, within five years of commencing closure activities pursuant to either 

paragraph (e)(1) or (e)(2) of this section.
Document submitted to conclude E.O.12866 Review

715

(2)(i) Extensions of closure timeframes. The timeframes for completing closure of a 

CCR unit specified under paragraphs (f)(1) of this section may be extended if the owner or 

operator can demonstrate that it was not feasible to complete closure of the CCR unit within the 

required timeframes due to factors beyond the facility’s control. If the owner or operator is 

seeking a time extension beyond the time specified in the written closure plan as required by 

paragraph (b)(1) of this section, the demonstration must include a narrative discussion providing 

the basis for additional time beyond that specified in the closure plan. The owner or operator 

must place each completed demonstration, if more than one time extension is sought, in the 

facility’s operating record as required by § 257.105(i)(6) prior to the end of any two-year period. 

Factors that may support such a demonstration include:

(A) Complications stemming from the climate and weather, such as unusual amounts 

of precipitation or a significantly shortened construction season;

(B) Time required to dewater a surface impoundment due to the volume of CCR 

contained in the CCR unit or the characteristics of the CCR in the unit;

(C) The geology and terrain surrounding the CCR unit will affect the amount of 

material needed to close the CCR unit; or 

(D) Time required or delays caused by the need to coordinate with and obtain 

necessary approvals and permits from a state or other agency.

(ii) Maximum time extensions. (A) CCR surface impoundments of 40 acres or 

smaller may extend the time to complete closure by no longer than two years.

(B) CCR surface impoundments larger than 40 acres may extend the timeframe to 

complete closure of the CCR unit multiple times, in two-year increments. For each two-year 

extension sought, the owner or operator must substantiate the factual circumstances 
Document submitted to conclude E.O.12866 Review

716

demonstrating the need for the extension. No more than a total of five two-year extensions may 

be obtained for any CCR surface impoundment.

(C) CCR landfills may extend the timeframe to complete closure of the CCR unit 

multiple times, in one-year increments. For each one-year extension sought, the owner or 

operator must substantiate the factual circumstances demonstrating the need for the extension. 

No more than a total of two one-year extensions may be obtained for any CCR landfill.

(iii) In order to obtain additional time extension(s) to complete closure of a CCR unit 

beyond the times provided by paragraph (f)(1) of this section, the owner or operator of the CCR 

unit must include with the demonstration required by paragraph (f)(2)(i) of this section the 

following statement signed by the owner or operator or an authorized representative:

I certify under penalty of law that I have personally examined and am 

familiar with the information submitted in this demonstration and all attached 

documents, and that, based on my inquiry of those individuals immediately 

responsible for obtaining the information, I believe that the submitted information 

is true, accurate, and complete. I am aware that there are significant penalties for 

submitting false information, including the possibility of fine and imprisonment.

(3) Upon completion, the owner or operator of the CCR unit must obtain a 

certification from a qualified professional engineer verifying that closure has been completed in 

accordance with the closure plan specified in paragraph (b) of this section and the requirements 

of this section.

(g) No later than the date the owner or operator initiates closure of a CCR unit, the 

owner or operator must prepare a notification of intent to close a CCR unit. The notification 

must include the certification by a qualified professional engineer for the design of the final 
Document submitted to conclude E.O.12866 Review

717

cover system as required by § 257.102(d)(3)(iii), if applicable. The owner or operator has 

completed the notification when it has been placed in the facility’s operating record as required 

by § 257.105(i)(7).

(h) Within 30 days of completion of closure of the CCR unit, the owner or operator 

must prepare a notification of closure of a CCR unit. The notification must include the 

certification by a qualified professional engineer as required by § 257.102(f)(3). The owner or 

operator has completed the notification when it has been placed in the facility’s operating record 

as required by § 257.105(i)(8).

(i) Deed notations. (1) Except as provided by paragraph (i)(4) of this section, 

following closure of a CCR unit, the owner or operator must record a notation on the deed to the 

property, or some other instrument that is normally examined during title search.

(2) The notation on the deed must in perpetuity notify any potential purchaser of the 

property that:

(i) The land has been used as a CCR unit; and

(ii) Its use is restricted under the post-closure care requirements as provided by § 

257.104(d)(1)(iii).

(3) Within 30 days of recording a notation on the deed to the property, the owner or 

operator must prepare a notification stating that the notation has been recorded. The owner or 

operator has completed the notification when it has been placed in the facility’s operating record 

as required by § 257.105(i)(9).

(4) An owner or operator that closes a CCR unit in accordance with paragraph (c) of 

this section is not subject to the requirements of paragraphs (i)(1) through (i)(3) of this section.
Document submitted to conclude E.O.12866 Review

718

(j) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(i), the notification requirements specified in § 257.106(i), 

and the internet requirements specified in § 257.107(i).

§ 257.103 Alternative closure requirements.

The owner or operator of a CCR landfill, CCR surface impoundment, or any lateral 

expansion of a CCR unit that is subject to closure pursuant to § 257.101(a), (b)(1), or (d) may 

continue to receive to receive CCR in the unit provided the owner or operator meets the 

requirements of either paragraph (a) or (b) of this section.

(a) (1) No alternative CCR disposal capacity. Notwithstanding the provisions of § 

257.101(a), (b)(1), or (d), a CCR unit may continue to receive CCR if the owner or operator of 

the CCR unit certifies that the CCR must continue to be managed in that CCR unit due to the 

absence of alternative disposal capacity both on-site and off-site of the facility. To qualify under 

this paragraph, the owner or operator of the CCR unit must document that all of the following 

conditions have been met: 

(i) No alternative disposal capacity is available on-site or off-site. An increase in 

costs or the inconvenience of existing capacity is not sufficient to support qualification under this 

section;

(ii) The owner or operator has made, and continues to make, efforts to obtain 

additional capacity. Qualification under this subsection lasts only as long as no alternative 

capacity is available. Once alternative capacity is identified, the owner or operator must arrange 

to use such capacity as soon as feasible;

(iii) The owner or operator must remain in compliance with all other requirements of 

this subpart, including the requirement to conduct any necessary corrective action; and
Document submitted to conclude E.O.12866 Review

719

(iv) The owner or operator must prepare an annual progress report documenting the 

continued lack of alternative capacity and the progress towards the development of alternative 

CCR disposal capacity.

(2) Once alternative capacity is available, the CCR unit must cease receiving CCR 

and initiate closure following the timeframes in § 257.102(e) and (f).

(3) If no alternative capacity is identified within 5 years after the initial certification, 

the CCR unit must cease receiving CCR and close in accordance with the timeframes in § 

257.102(e) and (f).

(b)(1) Permanent cessation of a coal-fired boiler(s) by a date certain. Notwithstanding 

the provisions of § 257.101(a), (b)(1), and (d), a CCR unit may continue to receive CCR if the 

owner or operator certifies that the facility will cease operation of the coal-fired boilers within 

the timeframes specified in paragraphs (b)(2) through (b)(4) of this section, but in the interim 

period (prior to closure of the coal-fired boiler), the facility must continue to use the CCR unit 

due to the absence of alternative disposal capacity both on-site and off-site of the facility. To 

qualify under this paragraph, the owner or operator of the CCR unit must document that all of the 

following conditions have been met:

(i) No alternative disposal capacity is available on-site or off-site. An increase in 

costs or the inconvenience of existing capacity is not sufficient to support qualification under this 

section.

(ii) The owner or operator must remain in compliance with all other requirements of 

this subpart, including the requirement to conduct any necessary corrective action; and
Document submitted to conclude E.O.12866 Review

720

(iii) The owner or operator must prepare an annual progress report documenting the 

continued lack of alternative capacity and the progress towards the closure of the coal-fired 

boiler.

(2) For a CCR surface impoundment that is 40 acres or smaller, the coal-fired boiler 

must cease operation and the CCR surface impoundment must have completed closure no later 

than [INSERT DATE 102 MONTHS AFTER DATE OF PUBLICATION IN THE 

FEDERAL REGISTER].

(3) For a CCR surface impoundment that is larger than 40 acres, the coal-fired boiler 

must cease operation, and the CCR surface impoundment must complete closure no later than 

[INSERT DATE 162 MONTHS AFTER DATE OF PUBLICATION IN THE FEDERAL 

REGISTER].

(4) For a CCR landfill, the coal-fired boiler must cease operation, and the CCR 

landfill must complete closure no later than [INSERT DATE 72 MONTHS AFTER DATE OF 

PUBLICATION IN THE FEDERAL REGISTER].

(c) Required notices and progress reports. An owner or operator of a CCR unit that 

closes in accordance with paragraphs (a) or (b) of this section must complete the notices and 

progress reports specified in paragraphs (c)(1) through (c)(3) of this section.

(1) Within six months of becoming subject to closure pursuant to § 257.101(a), 

(b)(1), or (d), the owner or operator must prepare and place in the facility’s operating record a 

notification of intent to comply with the alternative closure requirements of this section. The 

notification must describe why the CCR unit qualifies for the alternative closure provisions 

under either paragraph (a) or (b) of this section, in addition to providing the documentation and 

certifications required by paragraph (a) or (b) of this section.
Document submitted to conclude E.O.12866 Review

721

(2) The owner or operator must prepare the periodic progress reports required by 

paragraphs (a)(1)(iii) or (b)(1)(iii), in addition to describing any problems encountered and a 

description of the actions taken to resolve the problems. The annual progress reports must be 

completed according to the following schedule:

(i) The first annual progress report must be prepared no later than 13 months after 

completing the notification of intent to comply with the alternative closure requirements 

required by paragraph (c)(1) of this section.

(ii) The second annual progress report must be prepared no later than 12 months after 

completing the first annual progress report. Additional annual progress reports must be prepared 

within 12 months of completing the previous annual progress report.

(iii) The owner or operator has completed the progress reports specified in paragraphs 

(c)(2) of this section when the reports are placed in the facility’s operating record as required by 

§ 257.105(i)(10).

(3) An owner or operator of a CCR unit must also prepare the notification of intent to 

close a CCR unit as required by § 257.102(g).

(d) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(i), the notification requirements specified in § 257.106(i), 

and the internet requirements specified in § 257.107(i).

§ 257.104Post-closure care requirements.

(a) Applicability. (1) Except as provided by either paragraph (a)(2) or (a)(3) of this 

section, § 257.104 applies to the owners or operators of CCR landfills, CCR surface 

impoundments, and all lateral expansions of CCR units that are subject to the closure criteria 

under § 257.102.
Document submitted to conclude E.O.12866 Review

722

(2) An owner or operator of a CCR unit that elects to close a CCR unit by removing 

CCR as provided by § 257.102(c) is not subject to the post-closure care criteria under this 

section.

(3) An owner or operator of an inactive CCR surface impoundment that elects to 

close a CCR unit pursuant to the requirements under § 257.100(b) is not subject to the postclosure care criteria under this section.

(b) Post-closure care maintenance requirements. Following closure of the CCR unit, 

the owner or operator must conduct post-closure care for the CCR unit, which must consist of at 

least the following:

(1) Maintaining the integrity and effectiveness of the final cover system, including 

making repairs to the final cover as necessary to correct the effects of settlement, subsidence, 

erosion, or other events, and preventing run-on and run-off from eroding or otherwise damaging 

the final cover;

(2) If the CCR unit is subject to the design criteria under § 257.70, maintaining the 

integrity and effectiveness of the leachate collection and removal system and operating the 

leachate collection and removal system in accordance with the requirements of § 257.70; and

(3) Maintaining the groundwater monitoring system and monitoring the groundwater 

in accordance with the requirements of §§ 257.90 through 257.98.

(c) Post-closure care period. (1) Except as provided by paragraph (c)(2) of this 

section, the owner or operator of the CCR unit must conduct post-closure care for 30 years.

(2) If at the end of the post-closure care period the owner or operator of the CCR unit 

is operating under assessment monitoring in accordance with § 257.95, the owner or operator 
Document submitted to conclude E.O.12866 Review

723

must continue to conduct post-closure care until the owner or operator returns to detection 

monitoring in accordance with § 257.95.

(d) Written post-closure plan. (1) Content of the plan. The owner or operator of a 

CCR unit must prepare a written post-closure plan that includes, at a minimum, the information 

specified in paragraphs (d)(1)(i) through (d)(1)(iii) of this section.

(i) A description of the monitoring and maintenance activities required in paragraph 

(b) of this section for the CCR unit, and the frequency at which these activities will be 

performed;

(ii) The name, address, telephone number, and e-mail address of the person or office 

to contact about the facility during the post-closure care period; and

(iii) A description of the planned uses of the property during the post-closure period. 

Post-closure use of the property shall not disturb the integrity of the final cover, liner(s), or any 

other component of the containment system, or the function of the monitoring systems unless 

necessary to comply with the requirements in this subpart. Any other disturbance is allowed if 

the owner or operator of the CCR unit demonstrates that disturbance of the final cover, liner, or 

other component of the containment system, including any removal of CCR, will not increase the 

potential threat to human health or the environment. The demonstration must be certified by a 

qualified professional engineer, and notification shall be provided to the State Director that the 

demonstration has been placed in the operating record and on the owners or operator’s publicly 

accessible internet site.

(2) Deadline to prepare the initial written post-closure plan. (i) Existing CCR 

landfills and existing CCR surface impoundments. No later than [INSERT DATE 18 

MONTHS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER], the 
Document submitted to conclude E.O.12866 Review

724

owner or operator of the CCR unit must prepare an initial written post-closure plan consistent 

with the requirements specified in paragraph (d)(1) of this section.

(ii) New CCR landfills, new CCR surface impoundments, and any lateral expansion 

of a CCR unit. No later than the date of the initial receipt of CCR in the CCR unit, the owner or 

operator must prepare an initial written post-closure plan consistent with the requirements 

specified in paragraph (d)(1) of this section.

(iii) The owner or operator has completed the written post-closure plan when the plan, 

including the certification required by paragraph (d)(4) of this section, has been placed in the 

facility’s operating record as required by § 257.105(i)(4).

(3) Amendment of a written post-closure plan. (i) The owner or operator may amend 

the initial or any subsequent written post-closure plan developed pursuant to paragraph (d)(1) of 

this section at any time.

(ii) The owner or operator must amend the written closure plan whenever:

(A) There is a change in the operation of the CCR unit that would substantially affect 

the written post-closure plan in effect; or

(B) After post-closure activities have commenced, unanticipated events necessitate a 

revision of the written post-closure plan.

(iii) The owner or operator must amend the written post-closure plan at least 60 days 

prior to a planned change in the operation of the facility or CCR unit, or no later than 60 days 

after an unanticipated event requires the need to revise an existing written post-closure plan. If a 

written post-closure plan is revised after post-closure activities have commenced for a CCR unit, 

the owner or operator must amend the written post-closure plan no later than 30 days following 

the triggering event.
Document submitted to conclude E.O.12866 Review

725

(4) The owner or operator of the CCR unit must obtain a written certification from a 

qualified professional engineer that the initial and any amendment of the written post-closure 

plan meets the requirements of this section.

(e) Notification of completion of post-closure care period. No later than 60 days 

following the completion of the post-closure care period, the owner or operator of the CCR unit 

must prepare a notification verifying that post-closure care has been completed. The notification 

must include the certification by a qualified professional engineer verifying that post-closure care 

has been completed in accordance with the closure plan specified in paragraph (d) of this section 

and the requirements of this section. The owner or operator has completed the notification when 

it has been placed in the facility’s operating record as required by § 257.105(i)(13).

(f) The owner or operator of the CCR unit must comply with the recordkeeping 

requirements specified in § 257.105(i), the notification requirements specified in § 257.106(i), 

and the internet requirements specified in § 257.107(i).

Recordkeeping, Notification, and Posting of Information to the Internet

§ 257.105 Recordkeeping requirements.

(a) Each owner or operator of a CCR unit subject to the requirements of this subpart 

must maintain files of all information required by this section in a written operating record at 

their facility.

(b) Unless specified otherwise, each file must be retained for at least five years 

following the date of each occurrence, measurement, maintenance, corrective action, report,

record, or study.

(c) An owner or operator of more than one CCR unit subject to the provisions of this 

subpart may comply with the requirements of this section in one recordkeeping system provided 
Document submitted to conclude E.O.12866 Review

726

the system identifies each file by the name of each CCR unit. The files may be maintained on 

microfilm, on a computer, on computer disks, on a storage system accessible by a computer, on 

magnetic tape disks, or on microfiche. 

(d) The owner or operator of a CCR unit must submit to the State Director and/or 

appropriate Tribal authority any demonstration or documentation required by this subpart, if 

requested, when such information is not otherwise available on the owner or operator’s publicly 

accessible internet site.

(e) Location restrictions. The owner or operator of a CCR unit subject to this subpart 

must place the demonstrations documenting whether or not the CCR unit is in compliance with 

the requirements under §§ 257.60(a), 257.61(a), 257.62(a), 257.63(a), and 257.64(a), as it 

becomes available, in the facility’s operating record.

(f) Design criteria. The owner or operator of a CCR unit subject to this subpart must 

place the following information, as it becomes available, in the facility’s operating record:

(1) The design and construction certifications as required by § 257.70(e) and (f).

(2) The documentation of liner type as required by § 257.71(a).

(3) The design and construction certifications as required by § 257.72(c) and (d).

(4) Documentation prepared by the owner or operator stating that the permanent 

identification marker was installed as required by §§ 257.73(a)(1) and 257.74(a)(1).

(5) The initial and periodic hazard potential classification assessments as required by 

§§ 257.73(a)(2) and 257.74(a)(2).

(6) The emergency action plan (EAP), and any amendment of the EAP, as required 

by §§ 257.73(a)(3) and 257.74(a)(3), except that only the most recent EAP must be maintained in 
Document submitted to conclude E.O.12866 Review

727

the facility’s operating record irrespective of the time requirement specified in paragraph (b) of 

this section.

(7) Documentation prepared by the owner or operator recording the annual face-toface meeting or exercise between representatives of the owner or operator of the CCR unit and 

the local emergency responders as required by §§ 257.73(a)(3)(i)(E) and 257.74(a)(3)(i)(E).

(8) Documentation prepared by the owner or operator recording all activations of the 

emergency action plan as required by §§ 257.73(a)(3)(v) and 257.74(a)(3)(v).

(9) The history of construction, and any revisions of it, as required by § 257.73(c), 

except that these files must be maintained until the CCR unit completes closure of the unit in 

accordance with § 257.102.

(10) The initial and periodic structural stability assessments as required by §§ 

257.73(d) and 257.74(d).

(11) The action plan to remedy structural stability deficiencies as required by §§ 

257.73(d)(2) and 257.74(d)(2).

(12) The initial and periodic safety factor assessments as required by §§ 257.73(e) and 

257.74(e).

(13) The design and construction plans, and any revisions of it, as required by § 

257.74(c), except that these files must be maintained until the CCR unit completes closure of the 

unit in accordance with § 257.102.

(g) Operating criteria. The owner or operator of a CCR unit subject to this subpart 

must place the following information, as it becomes available, in the facility’s operating record:

(1) The CCR fugitive dust control plan, and any subsequent amendment of the plan, 

required by § 257.80(b), except that only the most recent control plan must be maintained in the 
Document submitted to conclude E.O.12866 Review

728

facility’s operating record irrespective of the time requirement specified in paragraph (b) of this 

section.

(2) The annual CCR fugitive dust control report required by § 257.80(c).

(3) The initial and periodic run-on and run-off control system plans as required by § 

257.81(c).

(4) The initial and periodic inflow design flood control system plan as required by § 

257.82(c). 

(5) Documentation recording the results of each inspection and instrumentation 

monitoring by a qualified person as required by § 257.83(a).

(6) The periodic inspection report as required by § 257.83(b)(2).

(7) The action plan as required by § 257.83(b)(5).

(8) Documentation recording the results of the weekly inspection by a qualified 

person as required by § 257.84(a).

(9) The periodic inspection report as required by § 257.84(b)(2).

(h) Groundwater monitoring and corrective action. The owner or operator of a CCR 

unit subject to this subpart must place the following information, as it becomes available, in the 

facility’s operating record:

(1) The annual groundwater monitoring and corrective action report as required by § 

257.90(e).

(2) Documentation of the design, installation, development, and decommissioning of 

any monitoring wells, piezometers and other measurement, sampling, and analytical devices as

required by § 257.91(e)(1).

(3) The groundwater monitoring system certification as required by § 257.91(f).
Document submitted to conclude E.O.12866 Review

729

(4) The selection of a statistical method certification as required by § 257.93(f)(6).

(5) Within 30 days of establishing an assessment monitoring program, the 

notification as required by § 257.94(e)(3).

(6) The results of the Appendix III to this part and Appendix IV to this part 

constituent concentrations as required by § 257.95(d)(1).

(7) Within 30 days of returning to a detection monitoring program, the notification as 

required by § 257.94(e).

(8) Within 30 days of detecting one or more constituents in Appendix IV to this part 

at statistically significant levels above the groundwater protection standard, the notifications as 

required by § 257.94(g) and (g)(2).

(9) Within 30 days of initiating the assessment of corrective measures requirements, 

the notification as required by § 257.95(g)(5).

(10) The completed assessment of corrective measures as required by § 257.96(d).

(11) Documentation prepared by the owner or operator recording the public meeting 

for the corrective measures assessment as required by § 257.96(e).

(12) The semiannual report describing the progress in selecting and designing the 

remedy and the selection of remedy report as required by § 257.97(a), except that the selection of 

remedy report must be maintained until the remedy has been completed.

(13) Within 30 days of completing the remedy, the notification as required by § 

257.98(e).

(i) Closure and post-closure care. The owner or operator of a CCR unit subject to 

this subpart must place the following information, as it becomes available, in the facility’s 

operating record:
Document submitted to conclude E.O.12866 Review

730

(1) The notification of intent to initiate closure of the CCR unit as required by § 

257.100(c)(1).

(2) The annual progress reports of closure implementation as required by § 

257.100(c)(2)(i) and (c)(2)(ii).

(3) The notification of closure completion as required by § 257.100(c)(3).

(4) The written closure plan, and any amendment of the plan, as required by § 

257.102(b), except that only the most recent closure plan must be maintained in the facility’s 

operating record irrespective of the time requirement specified in paragraph (b) of this section.

(5) The written demonstration(s), including the certification required by § 

257.102(e)(2)(iii), for a time extension for initiating closure as required by § 257.102(e)(2)(ii).

(6) The written demonstration(s), including the certification required by § 

257.102(f)(2)(iii), for a time extension for completing closure as required by § 257.102(f)(2)(i).

(7) The notification of intent to close a CCR unit as required by § 257.102(g).

(8) The notification of completion of closure of a CCR unit as required by § 

257.102(h).

(9) The notification recording a notation on the deed as required by § 257.102(i).

(10) The notification of intent to comply with the alternative closure requirements as 

required by § 257.103(c)(1).

(11) The annual progress reports under the alternative closure requirements as required 

by § 257.103(c)(2).

(12) The written post-closure plan, and any amendment of the plan, as required by § 

257.104(d), except that only the most recent closure plan must be maintained in the facility’s 

operating record irrespective of the time requirement specified in paragraph (b) of this section.
Document submitted to conclude E.O.12866 Review

731

(13) The notification of completion of post-closure care period as required by § 

257.104(e).

§ 257.106 Notification requirements.

(a) The notifications required under paragraphs (e) through (i) of this section must be 

sent to the relevant State Director and/or appropriate Tribal authority before the close of business 

on the day the notification is required to be completed. For purposes of this section, before the 

close of business means the notification must be postmarked or sent by electronic mail (e-mail). 

If a notification deadline falls on a weekend or federal holiday, the notification deadline is 

automatically extended to the next business day.

(b) If any CCR unit is located in its entirety within Indian Country, the notifications 

of this section must be sent to the appropriate Tribal authority. If any CCR unit is located in part 

within Indian Country, the notifications of this section must be sent both to the appropriate State 

Director and Tribal authority.

(c) Notifications may be combined as long as the deadline requirement for each 

notification is met.

(d) Unless otherwise required in this section, the notifications specified in this section 

must be sent to the State Director and/or appropriate Tribal authority within 30 days of placing in 

the operating record the information required by § 257.105.

(e) Location restrictions. The owner or operator of a CCR unit subject to the 

requirements of this subpart must notify the State Director and/or appropriate Tribal authority 

that each demonstration specified under § 257.105(e) has been placed in the operating record and 

on the owner or operator’s publicly accessible internet site.
Document submitted to conclude E.O.12866 Review

732

(f) Design criteria. The owner or operator of a CCR unit subject to this subpart must 

notify the State Director and/or appropriate Tribal authority when information has been placed in 

the operating record and on the owner or operator’s publicly accessible internet site. The owner 

or operator must:

(1) Within 60 days of commencing construction of a new CCR unit, provide 

notification of the availability of the design certification specified under § 257.105(f)(1) or (f)(3). 

If the owner or operator of the CCR unit elects to install an alternative composite liner, the owner 

or operator must also submit to the State Director and/or appropriate Tribal authority a copy of 

the alternative composite liner design.

(2) No later than the date of initial receipt of CCR by a new CCR unit, provide 

notification of the availability of the construction certification specified under § 257.105(f)(1) or 

(f)(3).

(3) Provide notification of the availability of the documentation of liner type 

specified under § 257.105(f)(2).

(4) Provide notification of the availability of the initial and periodic hazard potential 

classification assessments specified under § 257.105(f)(5).

(5) Provide notification of the availability of emergency action plan (EAP), and any 

revisions of the EAP, specified under § 257.105(f)(6).

(6) Provide notification of the availability of documentation prepared by the owner or 

operator recording the annual face-to-face meeting or exercise between representatives of the 

owner or operator of the CCR unit and the local emergency responders specified under § 

257.105(f)(7).
Document submitted to conclude E.O.12866 Review

733

(7) Provide notification of documentation prepared by the owner or operator 

recording all activations of the emergency action plan specified under § 257.105(f)(8).

(8) Provide notification of the availability of the history of construction, and any 

revision of it, specified under § 257.105(f)(9).

(9) Provide notification of the availability of the initial and periodic structural 

stability assessments specified under § 257.105(f)(10).

(10) Provide notification of the availability of the action plan to remedy structural 

stability deficiencies specified under § 257.105(f)(11).

(11) Provide notification of the availability of the initial and periodic safety factor 

assessments specified under § 257.105(f)(12).

(12) Provide notification of the availability of the design and construction plans, and 

any revision of them, specified under § 257.105(f)(13).

(g) Operating criteria. The owner or operator of a CCR unit subject to this subpart 

must notify the State Director and/or appropriate Tribal authority when information has been 

placed in the operating record and on the owner or operator’s publicly accessible internet site. 

The owner or operator must:

(1) Provide notification of the availability of the CCR fugitive dust control plan, or 

any subsequent amendment of the plan, specified under § 257.105(g)(1).

(2) Provide notification of the availability of the annual CCR fugitive dust control 

report specified under § 257.105(g)(2).

(3) Provide notification of the availability of the initial and periodic run-on and runoff control system plans specified under § 257.105(g)(3).
Document submitted to conclude E.O.12866 Review

734

(4) Provide notification of the availability of the initial and periodic inflow design 

flood control system plans specified under § 257.105(g)(4).

(5) Provide notification of the availability of the periodic inspection reports specified 

under § 257.105(g)(6).

(6) Provide notification of the availability of the action plan specified under § 

257.105(g)(7).

(7) Provide notification of the availability of the periodic inspection reports specified 

under § 257.105(g)(9).

(h) Groundwater monitoring and corrective action. The owner or operator of a CCR 

unit subject to this subpart must notify the State Director and/or appropriate Tribal authority 

when information has been placed in the operating record and on the owner or operator’s 

publicly accessible internet site. The owner or operator must:

(1) Provide notification of the availability of the annual groundwater monitoring and 

corrective action report specified under § 257.105(h)(1).

(2) Provide notification of the availability of the groundwater monitoring system 

certification specified under § 257.105(h)(3).

(3) Provide notification of the availability of the selection of a statistical method 

certification specified under § 257.105(h)(4).

(4) Provide notification that an assessment monitoring programs has been established 

specified under § 257.105(h)(5).

(5) Provide notification that the CCR unit is returning to a detection monitoring 

program specified under § 257.105(h)(7).
Document submitted to conclude E.O.12866 Review

735

(6) Provide notification that one or more constituents in Appendix IV to this part 

have been detected at statistically significant levels above the groundwater protection standard 

and the notifications to land owners specified under § 257.105(h)(8).

(7) Provide notification that an assessment of corrective measures has been initiated 

specified under § 257.105(h)(9).

(8) Provide notification of the availability of assessment of corrective measures 

specified under § 257.105(h)(10).

(9) Provide notification of the availability of the semiannual report describing the 

progress in selecting and designing the remedy and the selection of remedy report specified 

under § 257.105(h)(12).

(10) Provide notification of the completion of the remedy specified under § 

257.105(h)(13).

(i) Closure and post-closure care. The owner or operator of a CCR unit subject to 

this subpart must notify the State Director and/or appropriate Tribal authority when information 

has been placed in the operating record and on the owner or operator’s publicly accessible 

internet site. The owner or operator must: 

(1) Provide notification of the intent to initiate closure of the CCR unit specified 

under § 257.105(i)(1).

(2) Provide notification of the availability of the annual progress reports of closure 

implementation specified under § 257.105(i)(2).

(3) Provide notification of closure completion specified under § 257.105(i)(3).

(4) Provide notification of the availability of the written closure plan, and any 

amendment of the plan, specified under § 257.105(i)(4).
Document submitted to conclude E.O.12866 Review

736

(5) Provide notification of the availability of the demonstration(s) for a time 

extension for initiating closure specified under § 257.105(i)(5).

(6) Provide notification of the availability of the demonstration(s) for a time 

extension for completing closure specified under § 257.105(i)(6).

(7) Provide notification of intent to close a CCR unit specified under § 257.105(i)(7).

(8) Provide notification of completion of closure of a CCR unit specified under § 

257.105(i)(8).

(9) Provide notification of the deed notation as required by § 257.105(i)(9).

(10) Provide notification of intent to comply with the alternative closure requirements 

specified under § 257.105(i)(10).

(11) The annual progress reports under the alternative closure requirements as required 

by § 257.105(i)(11).

(12) Provide notification of the availability of the written post-closure plan, and any 

amendment of the plan, specified under § 257.105(i)(12).

(13) Provide notification of completion of post-closure care specified under § 

257.105(i)(13).

§ 257.107Publicly accessible internet site requirements.

(a) Each owner or operator of a CCR unit subject to the requirements of this subpart 

must maintain a publicly accessible internet site (CCR website) containing the information 

specified in this section. The owner or operator’s website must be titled “CCR Rule Compliance 

Data and Information.”

(b) An owner or operator of more than one CCR unit subject to the provisions of this 

subpart may comply with the requirements of this section by using the same internet site for 
Document submitted to conclude E.O.12866 Review

737

multiple CCR units provided the CCR website clearly delineates information by the name of 

each unit.

(c) Unless otherwise required in this section, the information required to be posted to 

the CCR website must be made available to the public for at least five years following the date 

on which the information was first posted to the CCR website.

(d) Unless otherwise required in this section, the information must be posted to the 

CCR website within 30 days of placing the pertinent information required by § 257.105 in the 

operating record.

(e) Location restrictions. The owner or operator of a CCR unit subject to this subpart 

must place each demonstration specified under § 257.105(e) on the owner or operator’s CCR 

website.

(f) Design criteria. The owner or operator of a CCR unit subject to this subpart must 

place the following information on the owner or operator’s CCR website:

(1) Within 60 days of commencing construction of a new unit, the design certification 

specified under § 257.105(f)(1) or (f)(3).

(2) No later than the date of initial receipt of CCR by a new CCR unit, the 

construction certification specified under § 257.105(f)(1) or (f)(3).

(3) The documentation of liner type specified under § 257.105(f)(2).

(4) The initial and periodic hazard potential classification assessments specified 

under § 257.105(f)(5).

(5) The emergency action plan (EAP) specified under § 257.105(f)(6), except that 

only the most recent EAP must be maintained on the CCR website irrespective of the time 

requirement specified in paragraph (c) of this section.
Document submitted to conclude E.O.12866 Review

738

(6) Documentation prepared by the owner or operator recording the annual face-toface meeting or exercise between representatives of the owner or operator of the CCR unit and 

the local emergency responders specified under § 257.105(f)(7).

(7) Documentation prepared by the owner or operator recording any activation of the 

emergency action plan specified under § 257.105(f)(8).

(8) The history of construction, and any revisions of it, specified under § 

257.105(f)(9).

(9) The initial and periodic structural stability assessments specified under § 

257.105(f)(10).

(10) The action plan to remedy structural stability deficiencies specified under § 

257.105(f)(11).

(11) The initial and periodic safety factor assessments specified under § 

257.105(f)(12).

(12) The design and construction plans, and any revisions of them, specified under § 

257.105(f)(13).

(g) Operating criteria. The owner or operator of a CCR unit subject to this subpart 

must place the following information on the owner or operator’s CCR website:

(1) The CCR fugitive dust control plan, or any subsequent amendment of the plan, 

specified under § 257.105(g)(1) except that only the most recent plan must be maintained on the 

CCR website irrespective of the time requirement specified in paragraph (c) of this section.

(2) The annual CCR fugitive dust control report specified under § 257.105(g)(2).

(3) The initial and periodic run-on and run-off control system plans specified under § 

257.105(g)(3).
Document submitted to conclude E.O.12866 Review

739

(4) The initial and periodic inflow design flood control system plans specified under 

§ 257.105(g)(4).

(5) The periodic inspection reports specified under § 257.105(g)(6).

(6) The action plan specified under § 257.105(g)(7).

(7) The periodic inspection reports specified under § 257.105(g)(9).

(h) Groundwater monitoring and corrective action. The owner or operator of a CCR 

unit subject to this subpart must place the following information on the owner or operator’s CCR 

website:

(1) The annual groundwater monitoring and corrective action report specified under § 

257.105(h)(1).

(2) The groundwater monitoring system certification specified under § 257.105(h)(3).

(3) The selection of a statistical method certification specified under § 257.105(h)(4).

(4) The notification that an assessment monitoring programs has been established 

specified under § 257.105(h)(5).

(5) The notification that the CCR unit is returning to a detection monitoring program 

specified under § 257.105(h)(7).

(6) The notification that one or more constituents in Appendix IV to this part have 

been detected at statistically significant levels above the groundwater protection standard and the 

notifications to land owners specified under § 257.105(h)(8).

(7) The notification that an assessment of corrective measures has been initiated 

specified under § 257.105(h)(9).

(8) The assessment of corrective measures specified under § 257.105(h)(10).
Document submitted to conclude E.O.12866 Review

740

(9) The semiannual reports describing the progress in selecting and designing remedy 

and the selection of remedy report specified under § 257.105(h)(12), except that the selection of 

the remedy report must be maintained until the remedy has been completed.

(10) The notification that the remedy has been completed specified under § 

257.105(h)(13).

(i) Closure and post-closure care. The owner or operator of a CCR unit subject to 

this subpart must place the following information on the owner or operator’s CCR website:

(1) The notification of intent to initiate closure of the CCR unit specified under § 

257.105(i)(1).

(2) The annual progress reports of closure implementation specified under § 

257.105(i)(2).

(3) The notification of closure completion specified under § 257.105(i)(3).

(4) The written closure plan, and any amendment of the plan, specified under § 

257.105(i)(4).

(5) The demonstration(s) for a time extension for initiating closure specified 

under § 257.105(i)(5).

(6) The demonstration(s) for a time extension for completing closure specified under 

§ 257.105(i)(6).

(7) The notification of intent to close a CCR unit specified under § 257.105(i)(7).

(8) The notification of completion of closure of a CCR unit specified under § 

257.105(i)(8).

(9) The notification recording a notation on the deed as required by § 257.105(i)(9).
Document submitted to conclude E.O.12866 Review

741

(10) The notification of intent to comply with the alternative closure requirements as 

required by § 257.105(i)(10).

(11) The annual progress reports under the alternative closure requirements as required 

by § 257.105(i)(11).

(12) The written post-closure plan, and any amendment of the plan, specified under § 

257.105(i)(12).

(13) The notification of completion of post-closure care specified under § 

257.105(i)(13).

5. Amend part 257 by adding “Appendix III to Part 257” and “Appendix IV to Part 257” 

to read as follows:

Appendix III to Part 257—Constituents for Detection Monitoring

Common Name1

Boron

Calcium

Chloride

Fluoride

pH

Sulfate

Total Dissolved Solids 

(TDS)

1 Common names are those widely used in government regulations, scientific 

publications, and commerce; synonyms exist for many chemicals.
Document submitted to conclude E.O.12866 Review

742

Appendix IV to Part 257—Constituents for Assessment Monitoring

Common Name1

Antimony

Arsenic

Barium

Beryllium

Cadmium

Chromium

Cobalt

Fluoride

Lead

Lithium

Mercury

Molybdenum

Selenium

Thallium

Radium 226 and 228 

combined

1 Common names are those widely used in government regulations, scientific 

publications, and commerce; synonyms exist for many chemicals.

PART 261—IDENTIFICATION AND LISTING OF HAZARDOUS WASTE
Document submitted to conclude E.O.12866 Review

743

6. The authority citation for part 261 continues to read as follows:

Authority: 42 U.S.C. 6905, 6912(a), 6921; 6922, 6924(y), and 6938.

7. Section 261.4 is amended by revising paragraph (b)(4) to read as follows:

§ 261.4 Exclusions.

* * * * *

(b) * * *

(4)(i) Fly ash waste, bottom ash waste, slag waste, and flue gas emission control waste 

generated primarily from the combustion of coal or other fossil fuels, except as provided by § 

266.112 of this chapter for facilities that burn or process hazardous waste.

(ii) The following wastes generated primarily from processes that support the 

combustion of coal or other fossil fuels that are co-disposed with the wastes in paragraph 

(b)(4)(i) of this section, except as provided by § 266.112 of this chapter for facilities that burn or 

process hazardous waste:

(A) Coal pile run-off. For purposes of paragraph (b)(4) of this section, coal pile runoff means any precipitation that drains off coal piles.

(B) Boiler cleaning solutions. For purposes of paragraph (b)(4) of this section, boiler 

cleaning solutions means water solutions and chemical solutions used to clean the fire-side and 

water-side of the boiler.

(C) Boiler blowdown. For purposes of paragraph (b)(4) of this section, boiler 

blowdown means water purged from boilers used to generate steam.

(D) Process water treatment and demineralizer regeneration wastes. For purposes of 

paragraph (b)(4) of this section, process water treatment and demineralizer regeneration wastes 
Document submitted to conclude E.O.12866 Review

744

means sludges, rinses, and spent resins generated from processes to remove dissolved gases, 

suspended solids, and dissolved chemical salts from combustion system process water. 

(E) Cooling tower blowdown. For purposes of paragraph (b)(4) of this section, 

cooling tower blowdown means water purged from a closed cycle cooling system. Closed cycle 

cooling systems include cooling towers, cooling ponds, or spray canals.

(F) Air heater and precipitator washes. For purposes of paragraph (b)(4) of this 

section, air heater and precipitator washes means wastes from cleaning air preheaters and 

electrostatic precipitators.

(G) Effluents from floor and yard drains and sumps. For purposes of paragraph (b)(4) 

of this section, effluents from floor and yard drains and sumps means wastewaters, such as wash 

water, collected by or from floor drains, equipment drains, and sumps located inside the power 

plant building; and wastewaters, such as rain runoff, collected by yard drains and sumps located 

outside the power plant building. 

(H) Wastewater treatment sludges. For purposes of paragraph (b)(4) of this section, 

wastewater treatment sludges refers to sludges generated from the treatment of wastewaters 

specified in paragraphs (b)(4)(ii)(A) through (b)(4)(ii)(F) of this section.

* * * * *